That sort of depends, but for the most part CSS frameworks can provide: - Sensible defaults for sizing and other attributes that tend to differ across browsers

That sort of depends, but for the most part CSS frameworks can provide: - Sensible defaults for sizing and other attributes that tend to differ across browsers, including typography and such (see Y! CSS Reset) - Helper classes for forms, info boxes, so on (see Blueprint's forms.css) - Grid-based layouts to cut down on dev time (see Y! Grids) Basically, they attempt to cut down on CSS development time by making things equivalent across browsers as well as providing many common styles you would have made anyway. Some also provide various grid-based layouts and others go beyond these things to provide even more, effectively creating something that truly is a framework (I prefer to think of most of them as CSS libraries).