Most people don't know the difference between the two art forms so I went online to see if I could find a good, concise explaination besides, one is with a hook and one is with two needles. . . I found this:
"One of the more obvious differences is that crochet uses one hook while most knitting uses two needles. This is because in crochet, the artisan usually has only one live stitch on the hook, while a knitter keeps an entire row of stitches active simultaneously. So dropped stitches, which can unravel a fabric, rarely interfere with crochet work. This is also because of a second, perhaps less obvious, structural difference between knitting and crochet. In knitting, each stitch is supported by the corresponding stitch in the row above and it supports the corresponding stitch in the row below. In crochet each stitch is only supported by and supports the stitches on either side of it. If a stitch in a finished item breaks, the stitches above and below remain intact, and, because of the complex looping of each stitch, the stitches on either side are not likely to come loose unless put under a lot of stress.
Round or cylindrical (This is crochet------>)patterns are simple to produce with a regular crochet hook, but cylindrical knitting requires either a set of circular needles or four or five special double sided needles. And free form crochet can create interesting shapes in several dimensions because new stitches can be made independently of previous stitches almost anywhere in the crocheted piece.
Knitting can be accomplished by machine, while many crochet stitches can only be crafted by hand. Although some crochet patterns can emulate the appearance of knitting, distinctive crochet patterns such as the Granny square cannot be simulated by other methods.
Crochet is more suitable than knitting for joining pieces of fabric and knit patterns for sweaters may incorporate crochet for finishing. Crochet can add borders or surface embellishment to both knit and crochet fabric. Crocheted fabric uses 1/3 more yarn than knitted fabric. Crochet produces a thicker fabric than knitting, and tends to have less "give" than knitted fabric. And, generally speaking, crochet technique produces fabric faster than knitting."
Not exactly what I'm going to tell someone who asks on the street, but some good information for myself and other enthusiasts who have searched for the "other" differences.
Personally, I think they look totally different, but I suppose I've been looking at them both for quite some time now. . .