There are several kinds of rights a publication may buy:

First North American Serial Rights—The newspaper or magazine has the right to publish this piece for the first time in any periodical. All other rights belong to the writer.

One-Time Rights—The publication buys the nonexclusive right to publish the piece once. The writer can sell the same article to other publications simultaneously.

Second Serial Rights (or Reprint Rights)—Also nonexclusive. Gives the publication the right to reprint an article that has appeared elsewhere.

Electronic Rights—Covers CD-ROMs, e-zines, website content, games, etc. Get in writing which electronic rights are specified-- First Electronic Rights, archiving rights, etc. Most publications ask for the right to archive "indefinitely." You can try to negotiate for a fixed term (i.e., archiving rights for six months).

All Rights—Pretty self-explanatory. You can never sell this piece to anyone else again. Try to avoid this one. Most publications ask for First Serial Rights.

Work-For-Hire Rights-- The publication has come up with the idea and assigned it to you, and they will own it, lock, stock, and barrel. They own the copyright and don't even have to give you credit. It may be sliced, diced, repackaged, re-sold, etc., and you won't have any claim to it beyond what you were originally paid.

TV/Motion Picture Rights—Also self-explanatory. Almost always exclusive.