ExtremeTech has published a guide to explain to newbies what Antialiasing and Anisotropic Filtering are:
We tend to throw around a lot of technical jargon and acronyms around here at ExtremeTech, and most of the time it's not a big deal. Our audience generally consists of people who know what we're talking about.
Having said that, we recognize that a fair number of readers pop in from time to time, coming in from sites like Digg or Slashdot, who aren't as versed in graphics terminology as some of our audience is. Even the most savvy computer enthusiasts can't always keep up with everything computers do these days. So with that in mind, we're going to take a few steps back today. Instead of drilling down deep on a particular bit of technology, we're going to give a broad, high-level overview of something fairly common that many computer users don't thoroughly understand.