Can a browser only render fonts installed on the system?

Question

For example - I see lot many different fonts on webpages.

Does the fact that I am able to view them mean that they all are installed on my system?

I do not think so. Then, how does my browser render them and show them to me?

Answer 1

If they're just there in plaintext, then yes, it should be installed. If they're not installed, the website is either using 1) an image, 2) a flash element to render the font, 3) css @font-face or 4) a canvas element.

Answer 2

Generally, the fonts are already installed on your system. However, there are two exceptions:

1) The webpage designer may use a CSS @font-face, which will attempt to load the font remotely. The browser may then cache the font for future use. Do note that this is somewhat unreliable at this time.

2) The webpage designer may have saved the text as an image. This is fairly common for cursive and other complicated fonts.