Sequence alignment

Sequence alignment is a way of comparing two sets of information, usually made up of letters (like A, T, G, and C). Sequence alignment let's us find similarities between these two sets of letters.
Think of it like a game of find-the-difference: We can look at the two sets of letters side-by-side, and see which letters are the same and which are different. The stuff that is the same is where we find the similarities.