bumping a thread brings it to the top of the forum. People will bump a discussion if it is not getting the attention they want. A bump simply moves a thread back up to the top of the forum so that others will remember to read and continue the discussion. For instance, you ask a question, no one responds for a day or so, and now you're thread is on page 12. Bumping will move it back to page 1 and someone will probably add to it.
(Detailed enough for a 4-letter word
Quote: "They are no stupid questions, just stupid people." - Mr. Garrison
(Quote wasn't meant to make fun of you aabby757... just a funny quote ... have to explain, sometimes my humor goes misunderstood here )