A clipping service sorts through journals, newspapers, and other publications; extracts the items of interest; bundles them together and drops the lot of them on your desk. You skim through the clippings. If there's something really interesting, you might save it. Often you'll run across an item that you know will interest someone else, so you pass it on to them, often with comments.
An aggregator takes a feed, generally published in the RSS format, collects it, collates it — optionally folds, spindles, and mutilates it — and presents it for your reading pleasure. Depending on the aggregator you use, some of these things will be more or less possible. But the general function is the same.
If there's something really interesting, you might save it. Often you'll run across an item that you know will interest someone else, so you pass it on to them, often with comments.
This post originally appeared here on May 22, 2002