A feed is an easy to use way of keeping up to date with lists of information on the web.
You normally subscribe to a feed using a feed reader which collects together all the feeds you subscribe to and also provides a way of unsubscribing should you get tired of a feed. Many browsers have feed readers built in, as do most email clients. In fact, a good way of thinking about feeds, is as a cross between subscribing to an email newsletter and regularly visiting website's news section.
In the past I have edited Volunteering magazine and the do-it.org.uk website and been chair of the trustees at Volunteer Centre Westminster.
I also write plays for radio and theatre.