| Year | Event |
| 1991 | id Software is founded February 1, 1991. |
| 1991 | BSDi is founded. |
| 1991 | Tim Berners-Lee introduces WWW to the public on August 6, 1991. |
| 1991 | NSF opens the Internet to commercial use. |
| 1991 | AMD introduces the AM386 microprocessor family in March. |
| 1991 | Intel introduces the Intel 486SX chip in April in efforts to help bring a lower-cost processor to the PC market selling for $258.00. |
| 1991 | Cell phone Lithium batteries begin being recalled in Japan after phone explodes and burns mans face while talking on the phone. |
| 1991 | The Sega Genesis game "Zero Wing" is introduced. The phrase "All your base are belong to us" later becomes a popular saying for computer gamers and geeks. |
| 1991 | Linux is introduced by Linus Torvald in 1991. Complete history on Linux can be found on our Linux / Unix history section. |
| 1991 | The World Wide Web is launched to the public August 6, 1991. Tim Berners-Lee, a scientist at the European Partial Physics Laboratory (CERN) in Geneva, Switzerland develops the Web as a research tool. |
| 1991 | Symantec releases Norton anti-virus software. |
| 1991 | The programming language FORTRAN 90 is created. |
| 1991 | Following its decision not to develop operating systems cooperatively with IBM, Microsoft changes the name of OS/2 to Windows NT. |
| 1991 | Creative Labs releases a multimedia upgrade kit that includes a CD-ROM drive, the SoundBlaster Pro sound card, a MIDI kit and a variety of software applications. The kit allows IBM compatible users to obtain all tools needed to meet the MPC standards. |
| 1991 | Pretty Good Privacy more commonly known as PGP a public key used for encryption is released as Freeware by Philip Zimmerman. |
| 1991 | The computer Monkey Virus is first discovered in Edmonton, Canada. |
| 1991 | The DLT tape drive is released as a very reliable, high-speed and high-capacity tape drive solution. |
| 1991 | The Enhanced Parallel Port (EPP) is developed by Intel, Xircom and Zenith Data Systems. |
| 1991 | TrueType a scalable font is introduced and developed by Microsoft and Apple and is used on all Apple computers and PC computers running Windows. |
| 1991 | MS-DOS 5.0 was released June, 1991. |
