The purl stitch seems to be harder for knitters to learn compared to the knit stitch. However, with a little practice it gets easier.
To create the purl stitch, take yarn around the right-hand needle and draw it through a stitch on the left-hand needle from the front of the stitch to the back to form the purl stitch. The needle enters the front of the stitch from back to front, and the yarn is held in front of the work is cast over needle back to front.
For me the purl stitch was harder to master then the knit stitch. I tried both the English and Continental styles of knitting the purl stitch. The English style seemed like wasted hand and wrist movement, so I prefer continental style knitting. However, with continental knitting I usually use the english method for the first stitch of the row because it is easier to create the stitch. But I still have difficulty with the Continental style of purling.
The blended or combination style of knitting and purling seems to be a a much easier and faster way of knitting and purling. Annie Modesitt has a website on Combined Knitting as well as a book called Confessions of a Knitting Heretic. She covers the basics of combination/blended style knitting with some great graphics and instructions.
When you knit on the right side of the fabric and purl on the wrong side of the fabric this creates the stockinette stitch pattern. The front side has the little Vs that we often associate with knitting and the back side has horizontal lines/bumps.
The combination of the knit stitch and the purl stitch is what creates all the lovely pattern stitches we have in knitting
Whatever style of stitch of purl stitch you do it is important to know how do it.
The abbreviation often used in patterns for purl is p.