Depends which side you're looking at it - the back of a knit is a purl, the back of a purl is a knit. The difference is which side faces you and how you make the stitch. Knitting all stitches every row is garter and when not stretched out can look like purls on both sides. Look on the Tips page for videos on the Basic stitches which show garter, stockinette, ribbing, etc.
sue- knitting heretic