The answer is: WJM

Mary Richards' professional home was WJM-TV, Channel 12 in Minneapolis – though calling it "professional" might be generous. The station consistently ranked dead last in ratings, thanks in no small part to Ted Baxter, the bumbling anchor whose ego was inversely proportional to his journalistic abilities.

The station's fictional call letters "WJM" became as iconic as Mary's famous hat toss in the opening credits. Though Minneapolis stations actually begin with 'K' (stations east of the Mississippi start with 'W', those west with 'K'), the show's creators chose WJM, perhaps because it rolled off the tongue better than KJIM.

What made WJM-TV revolutionary wasn't its broadcasting prowess but its portrayal of workplace dynamics. Before Mary Richards, television's working women were typically nurses or teachers waiting for marriage. Mary was different – she arrived at WJM after breaking off an engagement, took birth control (shocking for 1970), and valued her career ambitions over dating prospects.

When her boss Lou Grant asked in her interview, "You know what? You've got spunk," and followed it with "I hate spunk," it set the tone for seven seasons of a show that would tackle workplace sexism with humor rather than heavy-handedness. Mary earned promotions from associate producer to producer based on merit, demanded equal pay, and showed that being "nice" didn't mean being a pushover.

The newsroom itself became a blueprint for workplace comedy. Murray typed away at human interest pieces that somehow always involved cats. Lou Grant maintained his sanity through the strategic application of bottom-drawer whiskey. And Ted... well, Ted mangled news stories with the regularity of a broken teleprompter.

In the series finale, everyone except Ted was fired in a bid to boost ratings – a perfect punchline for a station that never quite got it right. The last newscast ended with the WJM team shuffling together in a group hug, singing "It's a Long Way to Tipperary." Fittingly, Ted mangled the lyrics.