A history of Windows

Highlights from the first 25 years

1975–1981: Microsoft boots up

Getting started: Microsoft co-founders Paul Allen (left) and Bill Gates

It’s the 1970s. At work, we rely on typewriters. If we need to copy a document, we likely use a mimeograph or carbon paper. Few have heard of microcomputers, but two young computer enthusiasts, Bill Gates and Paul Allen, see that personal computing is a path to the future.

In 1975, Gates and Allen form a partnership called Microsoft. Like most start-ups, Microsoft begins small, but has a huge vision—a computer on every desktop and in every home. During the next years, Microsoft begins to change the ways we work.

The dawn of MS‑DOS

In June 1980, Gates and Allen hire Gates’ former Harvard classmate Steve Ballmer to help run the company. The next month, IBM approaches Microsoft about a project code-named "Chess." In response, Microsoft focuses on a new operating system—the software that manages, or runs, the computer hardware and also serves to bridge the gap between the computer hardware and programs, such as a word processor. It’s the foundation on which computer programs can run. They name their new operating system "MS‑DOS."

When the IBM PC running MS‑DOS ships in 1981, it introduces a whole new language to the general public. Typing “C:” and various cryptic commands gradually becomes part of daily work. People discover the backslash (\) key.

MS‑DOS is effective, but also proves difficult to understand for many people. There has to be a better way to build an operating system.

Geek trivia: MS‑DOS stands for Microsoft Disk Operating System.

1982–1985: Introducing Windows 1.0

Microsoft works on the first version of a new operating system. Interface Manager is the code name and is considered as the final name, but Windows prevails because it best describes the boxes or computing “windows” that are fundamental to the new system. Windows is announced in 1983, but it takes a while to develop. Skeptics call it “vaporware.”

The fully-packaged Windows 1.0

On November 20, 1985, two years after the initial announcement, Microsoft ships Windows 1.0. Now, rather than typing MS‑DOS commands, you just move a mouse to point and click your way through screens, or “windows.” Bill Gates says, “It is unique software designed for the serious PC user…”

There are drop-down menus, scroll bars, icons, and dialog boxes that make programs easier to learn and use. You're able to switch among several programs without having to quit and restart each one. Windows 1.0 ships with several programs, including MS‑DOS file management, Paint, Windows Writer, Notepad, Calculator, and a calendar, card file, and clock to help you manage day-to-day activities. There’s even a game—Reversi.

Geek trivia: Remember floppy disks and kilobytes? Windows 1.0 requires a minimum of 256 kilobytes (KB), two double-sided floppy disk drives, and a graphics adapter card. A hard disk and 512 KB memory is recommended for running multiple programs or when using DOS 3.0 or higher.

1987–1992: Windows 2.0–2.11—More windows, more speed

On December 9, 1987 Microsoft releases Windows 2.0 with desktop icons and expanded memory. With improved graphics support, you can now overlap windows, control the screen layout, and use keyboard shortcuts to speed up your work. Some software developers write their first Windows–based programs for this release.

Windows 2.0

Windows 2.0 is designed for the Intel 286 processor. When the Intel 386 processor is released, Windows/386 soon follows to take advantage of its extended memory capabilities. Subsequent Windows releases continue to improve the speed, reliability, and usability of the PC.

In 1988, Microsoft becomes the world’s largest PC software company based on sales. Computers are starting to become a part of daily life for some office workers.

Geek trivia: Control Panel makes its first appearance in Windows 2.0.

1990–1994: Windows 3.0–Windows NT—Getting the graphics

On May 22, 1990, Microsoft announces Windows 3.0, followed shortly by Windows 3.1 in 1992. Taken together, they sell 10 million copies in their first 2 years, making this the most widely used Windows operating system yet. The scale of this success causes Microsoft to revise earlier plans. Virtual Memory improves visual graphics. In 1990 Windows starts to look like the versions to come.

Windows now has significantly better performance, advanced graphics with 16 colors, and improved icons. A new wave of 386 PCs helps drive the popularity of Windows 3.0. With full support for the Intel 386 processor, programs run noticeably faster. Program Manager, File Manager, and Print Manager arrive in Windows 3.0.

Bill Gates shows the newly-released Windows 3.0

Windows software is installed with floppy discs bought in large boxes with heavy instruction manuals.

The popularity of Windows 3.0 grows with the release of a new Windows software development kit (SDK), which helps software developers focus more on writing programs and less on writing device drivers.

Windows is increasingly used at work and home and now includes games like Solitaire, Hearts, and Minesweeper. An advertisement: “Now you can use the incredible power of Windows 3.0 to goof off.”

Windows for Workgroups 3.11 adds peer-to-peer workgroup and domain networking support and, for the first time, PCs become an integral part of the emerging client/server computing evolution.

Windows NT

When Windows NT releases on July 27, 1993, Microsoft meets an important milestone: the completion of a project begun in the late 1980s to build an advanced new operating system from scratch. "Windows NT represents nothing less than a fundamental change in the way that companies can address their business computing requirements," Bill Gates says at its release.

Unlike Windows 3.1, however, Windows NT 3.1 is a 32-bit operating system, which makes it a strategic business platform that supports high-end engineering and scientific programs.

Geek trivia: The group that develops Windows NT was originally called the "Portable Systems" team.

1995–2001: Windows 95—the PC comes of age (and don't forget the Internet)

On August 24, 1995, Microsoft releases Windows 95, selling a record-setting 7 million copies in the first five weeks. It’s the most publicized launch Microsoft has ever taken on. Television commercials feature the Rolling Stones singing "Start Me Up" over images of the new Start button. The press release simply begins: “It’s here.”

Launch day: Bill Gates introduces Windows 95

This is the era of fax/modems, e‑mail, the new online world, and dazzling multimedia games and educational software. Windows 95 has built-in Internet support, dial-up networking, and new Plug and Play capabilities that make it easy to install hardware and software. The 32-bit operating system also offers enhanced multimedia capabilities, more powerful features for mobile computing, and integrated networking.

At the time of the Windows 95 release, the previous Windows and MS‑DOS operating systems are running on about 80 percent of the world’s PCs. Windows 95 is the upgrade to these operating systems. To run Windows 95, you need a PC with a 386DX or higher processor (486 recommended) and at least 4 MB of RAM (8 MB of RAM recommended). Upgrade versions are available for both floppy disk and CD-ROM formats. It’s available in 12 languages.

Windows 95 features the first appearance of the Start menu, taskbar, and minimize, maximize, and close buttons on each window.

Windows 95

Catching the Internet wave

In the early 1990s, tech insiders are talking about the Internet—a network of networks that has the power to connect computers all over the world. In 1995, Bill Gates delivers a memo titled “The Internet Tidal Wave,” and declares the Internet as “the most important development since the advent of the PC.”

In the summer of 1995, the first version of Internet Explorer is released. The browser joins those already vying for space on the World Wide Web.

Geek trivia: In 1996, Microsoft releases Flight Simulator for Windows 95—the first time in its 14-year history that it’s available for Windows.

1998–2000: Windows 98, Windows 2000, Windows Me

Windows 98

Released on June 25, 1998, Windows 98 is the first version of Windows designed specifically for consumers. PCs are common at work and home, and Internet cafes where you can get online are popping up. Windows 98 is described as an operating system that “Works Better, Plays Better.”

With Windows 98, you can find information more easily on your PC as well as the Internet. Other improvements include the ability to open and close programs more quickly, and support for reading DVD discs and universal serial bus (USB) devices. Another first appearance is the Quick Launch bar, which lets you run programs without having to browse the Start menu or look for them on the desktop.

Geek trivia: Windows 98 is the last version based on MS‑DOS.

Windows 98

Windows Me

Designed for home computer use, Windows Me offers numerous music, video, and home networking enhancements and reliability improvements compared to previous versions.

First appearances: System Restore, a feature that can roll back your PC software configuration to a date or time before a problem occurred. Movie Maker provides users with the tools to digitally edit, save, and share home videos. And with Microsoft Windows Media Player 7 technologies, you can find, organize, and play digital media.

Geek trivia: Technically speaking, Windows Me was the last Microsoft operating system to be based on the Windows 95 code base. Microsoft announced that all future operating system products would be based on the Windows NT and Windows 2000 kernel.

Windows 2000 Professional

Windows 2000 Professional

More than just the upgrade to Windows NT Workstation 4.0, Windows 2000 Professional is designed to replace Windows 95, Windows 98, and Windows NT Workstation 4.0 on all business desktops and laptops. Built on top of the proven Windows NT Workstation 4.0 code base, Windows 2000 adds major improvements in reliability, ease of use, Internet compatibility, and support for mobile computing.

Among other improvements, Windows 2000 Professional simplifies hardware installation by adding support for a wide variety of new Plug and Play hardware, including advanced networking and wireless products, USB devices, IEEE 1394 devices, and infrared devices.

Geek trivia: The nightly stress test performed on Windows 2000 during development is the equivalent of three months of run time on up to 1,500 computers.

2001–2005: Windows XP—Stable, usable, and fast

On October 25, 2001, Windows XP is released with a redesigned look and feel that's centered on usability and a unified Help and Support services center. It’s available in 25 languages. From the mid-1970s until the release of Windows XP, about 1 billion PCs have been shipped worldwide.

For Microsoft, Windows XP will become one of its best-selling products in the coming years. It’s both fast and stable. Navigating the Start menu, taskbar, and Control Panel are more intuitive. Awareness of computer viruses and hackers increases, but fears are to a certain extent calmed by the online delivery of security updates. Consumers begin to understand warnings about suspicious attachments and viruses. There’s more emphasis on Help and Support.

Ship it: Windows XP Professional rolls to retail stores

Windows XP Home Edition offers a clean, simplified visual design that makes frequently used features more accessible. Designed for home use, Windows XP offers such enhancements as the Network Setup Wizard, Windows Media Player, Windows Movie Maker, and enhanced digital photo capabilities.

Windows XP Professional brings the solid foundation of Windows 2000 to the PC desktop, enhancing reliability, security, and performance. With a fresh visual design, Windows XP Professional includes features for business and advanced home computing, including remote desktop support, an encrypting file system, and system restore and advanced networking features. Key enhancements for mobile users include wireless 802.1x networking support, Windows Messenger, and Remote Assistance.

Windows XP has several editions during these years:

• Windows XP 64-bit Edition (2001) is the first Microsoft operating system for 64-bit processors designed for working with large amounts of memory and projects such as movie special effects, 3D animations, engineering, and scientific programs.
• Windows XP Media Center Edition (2002) is made for home computing and entertainment. You can browse the Internet, watch live television, enjoy digital music and video collections, and watch DVDs.
• Windows XP Tablet PC Edition (2002) realizes the vision of pen-based computing. Tablet PCs include a digital pen for handwriting recognition and you can use the mouse or keyboard, too.

Geek trivia: Windows XP is compiled from 45 million lines of code.

2006–2008: Windows Vista—Smart on security

Windows Vista is released in 2006 with the strongest security system yet. User Account Control helps prevent potentially harmful software from making changes to your computer. In Windows Vista Ultimate, BitLocker Drive Encryption provides better data protection for your computer, as laptop sales and security needs increase. Windows Vista also features enhancements to Windows Media Player as more and more people come to see their PCs as central locations for digital media. Here you can watch television, view and send photographs, and edit videos.

Windows Vista Ultimate

Design plays a big role in Windows Vista, and features such as the taskbar and the borders around windows get a brand new look. Search gets new emphasis and helps people find files on their PCs faster. Windows Vista introduces new editions that each have a different mix of features. It's available in 35 languages. The redesigned Start button makes its first appearance in Windows Vista.

Geek trivia: More than 1.5 million devices are compatible with Windows Vista at launch.

2009: Windows 7

Windows 7 was built for the wireless world that arose in the late 2000s. By the time it was released, laptops were outselling desktops, and it had become common to connect to public wireless hotspots in coffee shops and private networks in the home.

Windows 7 included new ways to work with windows—like Snap, Peek, and Shake—which both improved functionality and made the interface more fun to use. It also marked the debut of Windows Touch, which let touchscreen users browse the web, flip through photos, and open files and folders.

Improvements to the Windows 7 taskbar include live thumbnail previews

Geek trivia: Windows 7 was evaluated by 8 million beta testers worldwide before it was released.

2012: Windows 8

Windows 8 is Windows reimagined from the chipset to the user experience. It functions as both a tablet for entertainment and a full-featured PC for getting things done. It introduces a totally new interface that works smoothly for both touch and mouse and keyboard. Windows 8 also includes enhancements of the familiar Windows desktop, with a new taskbar and streamlined file management.

Windows 8 features a Start screen with tiles that connect to people, files, apps, and websites. Apps are front and center, with access to a new place to get apps—the Windows Store—built right in to the Start screen.

Along with Windows 8, Microsoft also launched Windows RT, which runs on some tablets and PCs. Windows RT is designed for sleek devices and long battery life, and exclusively runs apps from the Windows Store. It also comes with a built-in version of Office that's optimized for touchscreens.

Geek trivia: Power users will notice that Windows 8 has made the detection and correction of file system errors both more transparent and less intrusive.

Integrated Circuits
Our world is full of integrated circuits. You find several of them in computers. For example, most people have probably heard about the microprocessor. The microprocessor is an integrated circuit that processes all information in the computer. It keeps track of what keys are pressed and if the mouse has been moved. It counts numbers and runs programs, games and the operating system. Integrated circuits are also found in almost every modern electrical device such as cars, television sets, CD players, cellular phones, etc. But what is an integrated circuit and what is the history behind it?

Photo: Nobelprize.org

Electric Circuits
The integrated circuit is nothing more than a very advanced electric circuit. An electric circuit is made from different electrical components such as transistors, resistors, capacitors and diodes, that are connected to each other in different ways. These components have different behaviors.
The transistor acts like a switch. It can turn electricity on or off, or it can amplify current. It is used for example in computers to store information, or in stereo amplifiers to make the sound signal stronger.
The resistor limits the flow of electricity and gives us the possibility to control the amount of current that is allowed to pass. Resistors are used, among other things, to control the volume in television sets or radios.
The capacitor collects electricity and releases it all in one quick burst; like for instance in cameras where a tiny battery can provide enough energy to fire the flashbulb.
The diode stops electricity under some conditions and allows it to pass only when these conditions change. This is used in, for example, photocells where a light beam that is broken triggers the diode to stop electricity from flowing through it.
These components are like the building blocks in an electrical construction kit. Depending on how the components are put together when building the circuit, everything from a burglar alarm to a computer microprocessor can be constructed.

The Transistor vs. the Vacuum Tube
Of the components mentioned above, the transistor is the most important one for the development of modern computers. Before the transistor, engineers had to use vacuum tubes. Just as the transistor, the vacuum tube can switch electricity on or off, or amplify a current. So why was the vacuum tube replaced by the transistor? There are several reasons.
The vacuum tube looks and behaves very much like a light bulb; it generates a lot of heat and has a tendency to burn out. Also, compared to the transistor it is slow, big and bulky.

The vacuum tube and the transistor. Photo: Nobelprize.org	ENIAC-The first digital computer Photo: U.S Army

When engineers tried to build complex circuits using the vacuum tube, they quickly became aware of its limitations. The first digital computer ENIAC, for example, was a huge monster that weighed over thirty tons, and consumed 200 kilowatts of electrical power. It had around 18,000 vacuum tubes that constantly burned out, making it very unreliable.
When the transistor was invented in 1947 it was considered a revolution. Small, fast, reliable and effective, it quickly replaced the vacuum tube. Freed from the limitations of the vacuum tube, engineers finally could begin to realize the electrical constructions of their dreams, or could they?

The Tyranny of Numbers
With the small and effective transistor at their hands, electrical engineers of the 50s saw the possibilities of constructing far more advanced circuits than before. However, as the complexity of the circuits grew, problems started arising.
When building a circuit, it is very important that all connections are intact. If not, the electrical current will be stopped on its way through the circuit, making the circuit fail. Before the integrated circuit, assembly workers had to construct circuits by hand, soldering each component in place and connecting them with metal wires. Engineers soon realized that manually assembling the vast number of tiny components needed in, for example, a computer would be impossible, especially without generating a single faulty connection.
Another problem was the size of the circuits. A complex circuit, like a computer, was dependent on speed. If the components of the computer were too large or the wires interconnecting them too long, the electric signals couldn't travel fast enough through the circuit, thus making the computer too slow to be effective.
So there was a problem of numbers. Advanced circuits contained so many components and connections that they were virtually impossible to build. This problem was known as the tyranny of numbers.

Jack Kilby's Chip - the Monolithic Idea

Jack S Kilby Photo: Texas Instruments	Kilbys first chip Photo: Texas Instruments

In the summer of 1958 Jack Kilby at Texas Instruments found a solution to this problem. He was newly employed and had been set to work on a project to build smaller electrical circuits. However, the path that Texas Instruments had chosen for its miniaturization project didn't seem to be the right one to Kilby.
Because he was newly employed, Kilby had no vacation like the rest of the staff. Working alone in the lab, he saw an opportunity to find a solution of his own to the miniaturization problem. Kilby's idea was to make all the components and the chip out of the same block (monolith) of semiconductor material. When the rest of the workers returned from vacation, Kilby presented his new idea to his superiors. He was allowed to build a test version of his circuit. In September 1958, he had his first integrated circuit ready. It was tested and it worked perfectly!
Although the first integrated circuit was pretty crude and had some problems, the idea was groundbreaking. By making all the parts out of the same block of material and adding the metal needed to connect them as a layer on top of it, there was no more need for individual discrete components. No more wires and components had to be assembled manually. The circuits could be made smaller and the manufacturing process could be automated.
Jack Kilby is probably most famous for his invention of the integrated circuit, for which he received the Nobel Prize in Physics in the year 2000. After his success with the integrated circuit Kilby stayed with Texas Instruments and, among other things, he led the team that invented the hand-held calculator.

Robert Noyce

Robert Noyce Photo: Intel Museum Archives

Robert Noyce came up with his own idea for the integrated circuit. He did it half a year later than Jack Kilby. Noyce's circuit solved several practical problems that Kilby's circuit had, mainly the problem of interconnecting all the components on the chip. This was done by adding the metal as a final layer and then removing some of it so that the wires needed to connect the components were formed. This made the integrated circuit more suitable for mass production. Besides being one of the early pioneers of the integrated circuit, Robert Noyce also was one of the co-founders of Intel. Intel is one of the largest manufacturers of integrated circuits in the world.

Chip Production Today - in Short

Stepping.

Chip production today is based on photolithography. In photolithography a high energy UV-light is shone through a mask onto a slice of silicon covered with a photosensitive film. The mask describes the parts of the chip and the UV-light will only hit the areas not covered by the mask. When the film is developed, the areas hit by light are removed. Now the chip has unprotected and protected areas forming a pattern that is the first step to the final components of the chip.
Next, the unprotected areas are processed so their electrical properties change. A new layer of material is added, and the entire process is then repeated to build the circuit, layer by layer. When all the components have been made and the circuit is complete a layer of metal is added. Just as before, a layer of photosensitive film is applied and exposed through a mask. However, this time the mask used describes the layout of the wires connecting all the parts of the chip. The film is developed and the unexposed parts are removed. Next, the metal not protected with film is removed to form the wires. Finally, the chip is tested and packaged.
When making chips today, a process called "stepping" is often used. On a big wafer of silicon the chips are made one next to the other. The silicon wafer is moved in steps under the mask and the UV-light to expose the wafer. In this way, chip after chip can be made using the same mask each time.
Below is a more sequential description of the process of making a modern integrated circuit. But let us first take a look at the special place where integrated circuits are produced - the clean room.

The Clean Room

Child facing "bunny suit" Photo: Intel Museum Archives

The sizes of the components on chips produced in a modern chip fabrication plant are extremely small. For a better understanding of how small they are, pick a hair from your head and cut it in half. Now look at the cross section. On this tiny area, hard to see with the bare eye, you can fit thousands of modern transistors.
With sizes this small, the production of a chip demands precision at an atomic level. Tiny particles like a hair, a speck of dust, a dead skin cell, bacteria or even the single particles in tobacco smoke become huge objects that are big enough to ruin a chip.
Therefore, chip production takes place in a clean room. This is a specially designed room, where furniture is built from special materials that don't give off particles, and where extremely effective air filters and air circulation systems change the air completely up to ten times a minute.
To further prevent contamination, workers wear special suits called "bunny suits." These protective outfits are made of ultra clean material and sometimes have their own air filtering systems.

Chip Production Today - in Detail
Building an integrated circuit like a computer chip is a very complex process. It is divided into two major parts, front end and back end. In the front end, you make the components of the circuit. In the back end, you add metal to connect the components and then you test and package the chip. Below is a simplified description of the steps.

Front End – Construction of the Components

	1. Just as in building a house, you need a construction plan to construct a chip. The construction plans for the chip are made and tested with a computer.
	2. From the construction plans, masks with the circuit patterns are made.
	3. Under precisely monitored conditions, a pure silicon crystal is grown. Circuit manufacturing demands the use of crystals with an extremely high grade of perfection.
	4. The silicon is sawed into thin wafers with a diamond saw. The wafers are then polished in a number of steps until their surface has a perfect mirror-like finish
	5. The silicon wafer is covered with a layer of insulating silicon oxide.
	6. A covering film of protective material is put on top of the insulating silicon oxide. This material, a bit like the film in any ordinary camera, is sensitive to light.
	7. UV-light is shone through a mask and onto the chip. On the parts of the chip that are hit by light, the protective material breaks apart.
	8. The wafer is developed, rinsed and baked. The development process removes the parts of the protective material exposed to light.
	9. The wafer is treated with chemicals in a process called "etching." This removes the unprotected insulating material, creating a pattern of non-protected silicon wafer parts surrounded by areas protected by silicon oxide.
	10. The wafer is run through a process that alters the electrical properties of the unprotected areas of the wafer. This process is called "doping." Steps 5-10 are repeated to build the integrated circuit, layer by layer. Other layers of conducting or isolating layers may also be added to make the components.
	Back End – Adding the Connecting Wires
	11. Finally, when all the components of the chip are ready, metal is added to connect the components to each other in a process called metalization. This is done in a way similar to the making of the components. First a conducting metal like copper is deposited over the chip.
	12. On top of the metal a layer of UV-sensitive photo resist is added.
	13. Next, a mask that describes the desired layout of the metal wires connecting the components of the chip is used. UV-light is shone through this mask. The light hits the photo resist that isn't protected by the mask.
	14. In the next step, chemicals are used to remove the photo resist hit by UV-light.
	15. Another step of etching removes the metal not protected by photo resist.
	16. This leaves a pattern of metal that is the same as the one described by the mask. Now, the chip has a layer of wires that connect its different components.
	17. Today, most integrated circuits need more than one layer of wires. Advanced circuits may need up to five different layers of metal to form all the necessary connections. In the last picture we have added another layer of metal to our example. As you can see, a layer of insulating material is put between the two metal layers to prevent the wires from connecting in the wrong places. Of course, to add the second layer we had to go through the same steps as when adding the first layer of metal.
	18. When the final layer of connecting metal wires have been added, the chips on the silicon wafer are tested to see if they perform as intended.
	19. The chips on the wafer are separated with a diamond saw to form individual integrated circuits.
	20. Finally, each chip is packed into the protective casing and subjected to another series of tests. The chip is now finished and ready to be shipped to manufacturers of digital devices around the world.

The Evolution of the Integrated Circuit
The integrated circuit has come a long way since Jack Kilby's first prototype. His idea founded a new industry and is the key element behind our computerized society. Today the most advanced circuits contain several hundred millions of components on an area no larger than a fingernail. The transistors on these chips are around 90 nm, that is 0.00009 millimeters*, which means that you could fit hundreds of these transistors inside a red blood cell.

Jack Kilby examines a wafer filled with chips. Photo: Texas Instruments

Each year computer chips become more powerful yet cheaper than the year before. Gordon Moore, one of the early integrated circuit pioneers and founders of Intel once said, "If the auto industry advanced as rapidly as the semiconductor industry, a Rolls Royce would get a half a million miles per gallon, and it would be cheaper to throw it away than to park it."**
*1 inch = 25.4 millimeters
**1 US gallon = 3.8 litres, 1 mile = 1.6 km