Web safe fonts are fonts that are pre-installed by many operating systems. While not all systems have the same fonts installed, you can use a web safe font stack to choose several fonts that look similar, and are installed on the various systems that you want to support. If you want to use fonts other than ones pre-installed, as of CSS3, you can use Web Fonts.
What are Web Fonts?
Unlike web safe fonts, web fonts are not pre-installed on the user’s system. The fonts are downloaded by the user’s browser while rendering the webpage, and then applied to your text. The main drawbacks of using web fonts is it will slow your site’s load time. There is also limited support for CSS3 in older browsers which is required to use web fonts. The later limitation can be remedied by using a font stack, similar to the web safe font stacks, but including a web font as the first font of the stack. If a browser is unable to use the web font it will fall back on the web safe fonts in the stack.
Free fonts are notorious for being of low quality. Just because it is available on Google Fonts or Adobe TypeKit does not automatically guarantee anything other than it can be utilized as a web font with out uploading to your site’s server with the @font face CSS code.