Bootstrap includes over 250 glyphs in font format from the Glyphicon Halflings set. Glyphicons Halflings are normally not available for free, but we thank their creator for making them available with Bootstrap free of cost.

Because Glyphicons are font based, they scale cleanly both up and down. You can, for example, zoom in on this page to see them in various sizes. (Friendly reminder that Ctrl + 0 will then reset your zoom to normal.)