Just a little side-note you might find interesting:
In the home computer era, when 8x8 bitmap fonts had their heyday, displays often had rectangular pixels. So, while the characters look square now, they often did not back then.
Most of the 8-bit machines had quite square pixels (Spectrum, Commodore 64) but machines with multiple resolutions often had modes that doubled the horizontal res (C128, PCW, BBC Mode 3) giving rectangular pixels and by the time the 16-bits hit (Amiga, Atari ST) these modes were commonly the default and square pixels were relegated to "low-res" modes which were used less often.
The Commodore 64 (I still have mine) has a ratio of about 1.3 on NTSC, so not quite your average web-font (which are around 2 or higher), but hardly square.
In the home computer era, when 8x8 bitmap fonts had their heyday, displays often had rectangular pixels. So, while the characters look square now, they often did not back then.