yes, a rib stitch alternates knit with purl:
k1, p,1,k1,p1,... or k2,p2,k2,p2,... etc.
BUT!!! you must start with an even number of stitches. For example, cast on 10, 12, 14, 20, ... stitches.
If you cast on an odd number of stitiches and follow the same alternating stitch pattern, you will get a seed stitch (otherwise known as moss stitch and, I think, sand stitch)
I hop this helps. You will see the ribs within a few rows. If you use a real nubby yarn the look may not be as dramatic. I think it is important to consider the yarn AND the stitch so that each compliments the other rather than competing for the limelight.