Through several jobs in the electronics industry, he was working as an engineer at Sanders Associates (now BAE Systems)[2] in Nashua, New Hampshire, when he conceived the idea of playing games on a television screen around 1966.

[3] In February 2006, he was awarded the National Medal of Technology for "his groundbreaking and pioneering creation, development and commercialization of interactive video games, which spawned related uses, applications, and mega-industries in both the entertainment and education realms".

In 1943 he was drafted to fight in World War II and assigned to military intelligence at the United States Army headquarters in London.

[18] On returning from war duty in 1946, he presented a large collection of weaponry he had amassed (about 18 short tons (16,000 kg)) to museums in Aberdeen, Maryland; Springfield, Massachusetts; and Fort Riley, Kansas.

There he designed and built surgical cutting machines, epilators, and low frequency pulse generating muscle-toning equipment.

In 1951, Baer went to work as a senior engineer for Loral Electronics in Bronx, New York, where he designed power line carrier signaling equipment, contracting for IBM.

[22] He started his own company before joining defense contractor Sanders Associates in Nashua, New Hampshire (now part of BAE Systems Inc.) in 1956, where he stayed until retiring in 1987.

[26] His son, Mark, helped lead the nomination process to elevate him to become an IEEE Life Fellow, the highest level of membership within the organization.

[17][28] In 1966, while an employee at Sanders Associates, Baer started to explore the possibility of playing games on television screens.

[30] Upon coming up with the idea of creating a game using the television screen, he wrote a four-page proposal with which he was able to convince one of his supervisors to allow him to proceed.

[44][45] On February 13, 2006, Baer was awarded the National Medal of Technology by President George W. Bush in honor of his "groundbreaking and pioneering creation, development and commercialization of interactive video games".

[46][47] On April 1, 2010, Baer was inducted into the National Inventors Hall of Fame at a ceremony at the United States Department of Commerce in Washington, D.C.[48] While Baer's contributions had generally been overlooked by more recent advances in video game technology development, Baer had stated "In view of the fact that the President of the United States of America hung the National Medal of Technology around my neck in a White House ceremony in 2006, and in view of my having been inducted into the National Inventors Hall of Fame, I really don't feel neglected.

On April 8, 2021, the United States Mint announced that Baer and "Handball" would be honored as part of the American Innovation dollars program.