The Courier. It's a classic. Everybody would have seen it. How could they not? IBM commissioned in the 1950s for use in its typewriters it rapidly spread to become the de facto standard for typewriters. So naturally it's a standard on even the most basic word processors. It's up there with the greats - Arial and Times New Roman.
But I hate it. I used to like it when I actually typed on typewriters but not these days. It's fat, takes up a lot of space, awfully square and fearsomely predictable. And not just I think so. The US State Department changed its standard typeface from 12 point Courier New to 14 point Times New Roman citing the desire for a more modern and legible font. Yeah, Yeah. The Americans get an A plus for giving some formal bullshit for a straightforward and simple answer.
Basically, it's ugly.