Not a stupid question. An * indicates that the following stitches will be repeated either a given number of times, till you reach the end of the row, or a certain number of stitches remain.
K1, p2 *k2, p2 repeat from * to last stitch, k1
would give you ribbing with an edge stitch at each end.
Sometimes there will be an * at each end of a set of stitches and they will be repeated as instructed. ( ) and [ ] are used similarly.