Charles Matthew Geschke was born in Cleveland, Ohio, on September 11, 1939. He attended Saint Ignatius High School.
Geschke earned an AB in classics in 1962 and an MS in mathematics in 1963, both from

Geschke started working at Xerox's Palo Alto Research Center (PARC) in October 1972. His first project was to build a mainframe computer. Afterward, he worked on programming

In 1999, Geschke was inducted as a fellow of the Association for Computing Machinery (ACM).
In 2002, he was made a fellow of the Computer History Museum

Geschke was a Catholic and met his wife Nancy "Nan" McDonough at a religious conference on social action in the spring of 1961. They married in 1964. Both were graduates of Catholic institutions. In 2012 they received the St. Elizabeth Ann Seton Award from the

On the morning of May 26, 1992, as Geschke was arriving for work in Mountain View, California, he was kidnapped at gunpoint from the Adobe parking lot by two men, Mouhannad Albukhari, 26, of San Jose, and Jack Sayeh, 25, of Campbell. A spokesperson for the FBI

Geschke served on the boards of the San Francisco Symphony, the National Leadership Roundtable on Church Management, the Commonwealth Club of California, Tableau Software, the Egan Maritime Foundation, and the Nantucket Boys and Girls Club. He

Geschke, a longtime resident of Los Altos, died on April 16, 2021, at the age of 81. The cause of death was cancer.
He is survived by his wife, three children and seven grandchildren.