Helvetica

Helvetica is the font most used by designers, but why is that?

Created in 1957, Helvetica has been popular ever since. It's popularity could be due to the fact it's one of the most readable fonts available. It's type is the simplist, yet still complimentary of each other (the i and j for example). The font works well regardless of kerning and still remains readable, and it can be used on nearly anything for any subject matter. It's a chameleon of fonts: with no intrinsic meaning or fanciful flourishes within the font, it can become whatever it needs to be for different projects/ads/etc. It's a font you could use on anything and 9 times out of 10 will looks great and undistracting and complimentary.