"HCF" ("Halt and Catch Fire") is from one of a number of lists of humourous assembly command mnemonics. Others are "BrH" ("Branch and Hang" and "DWIM" ("Do What I Meant"). {DWIM, if it existed, would be the single most useful programming command ever.}

Scoot McNairy and Kerry Bishe co-star as husband and wife, Gordon and Donna Clark. They also appeared as husband and wife, Joe and Kathy Stafford, in Argo.

In an interview for The Guardian, Lee Pace references Steve Jobs, Patrick Bateman and Don Draper as influences for his portrayal of character Joe Macmillan.

Scoot McNairy (Gordon Clark) interviewed computer engineers to see what their personal and professional quirks were. He then applied some of these findings to help ground his character.

While the first two seasons were set in Grand Prairie of the DFW Metroplex, the show is filmed in Atlanta, Georgia. In particular, Atlanta's tallest skyscraper, the Bank of America Plaza, doubles as the headquarters for Westgroup Energy.

In season 4's "Who Needs A Guy?" Alana Cavanaugh's actual sister Farah plays the younger version of Haley as Alana outgrew the role.

Due to the Time Skip at the end of Season 3, Haley and Joanie Clark each had two different actresses. Alana Cavanaugh and Morgan Hinkleman portrayed Haley and Joanie as children respectively in the first 28 episodes while Susanna Skaggs and Kathryn Newton take up the roles as teenagers in the final 12 episodes of the series.

Joe's first and last line in the series is "let me start by asking a question"