January 1. The MITS Altair 8800 appears on the cover of Popular Electronics, inspiring Paul Allen and Bill Gates to develop a BASIC language for the Altair.
February 1. Bill Gates and Paul Allen sell BASIC, the first computer language program for a personal computer, to Microsoft's first customer, MITS of Albuquerque, NM.
March 1. Paul Allen joins MITS as director of software.
April 7. "Altair BASIC‑Up and Running," declares the headline of the first edition of MITS Computer Notes.
July 1. BASIC officially ships as version 2.0 in both 4K and 8K editions.
February 3. Bill Gates is one of the first programmers to raise the issue of software piracy. In "An Open Letter to Hobbyists," first published in MITS Computer Notes, Gates accuses hobbyists of stealing software and thus preventing "...good software from being written." He prophetically concludes with the line, "...Nothing would please me more than being able to hire ten programmers and deluge the hobby market with good software."
March 27. Bill Gates gives the opening address at the First Annual World Altair Computer Convention, held in Albuquerque.
November 1. Paul Allen resigns from MITS to join Microsoft full time.
November 26. The trade name Microsoft is registered with the Office of the Secretary of the State of New Mexico.
February 3. Paul Allen and Bill Gates execute an official partnership agreement.
July 1. FORTRAN-80, Microsoft's second language product, is available.
November 1. Microsoft establishes its first international sales office in Japan, ASCII Microsoft.
December 31. Microsoft's year-end sales exceed $1 million.
January 1. Microsoft moves its offices to Bellevue, WA, from Albuquerque.