As we dig into type rendering on the web, we’ll begin by looking at text rendering engines. We are all familiar with operating systems like Windows and Mac OS X, but within each OS are smaller, specialized components available for use by applications like web browsers. APIs such as Core Text on Mac OS X, and DirectWrite and GDI on Windows, are examples of these components and are responsible for rasterizing fonts’ vector outlines. Let’s examine screenshots of web type as rendered by each of these APIs, and talk about the application independence of rendering engines.
via The Typekit Blog – Type rendering: operating systems. How does type get rendered on Macs (also iOS devices) and Windows and what is each platform aiming for?