Loops are an integral part of crocheting. The following resources will help you understand loops and how to work with them while crocheting.
Front and Back Loops
What does "back loop only" mean? If you've encountered this perplexing phrase in a crochet pattern, and you have no idea what it means, this page will help. The page includes pictures plus examples and free crochet patterns you can use for practice with crocheting into the back loops of your stitches.
If you'd like to see a crochet teacher demonstrating which loops are the front loops vs which loops are the back loops, check out this free video at the video.about.com website.
If you'd like a more in-depth look at how to crochet through loops, this tutorial is the page to look at. There is also a practice project that accompanies this tutorial; once you've completed the tutorial, be sure to use what you've learned by making a pair of sunset pebbles wrist warmers.
If you'd rather try a quicker project, check out this textured washcloth pattern.
Have you encountered instructions to "pull up a loop" or "draw up a loop"? If you have no idea what these instructions mean, this page will help.
What does it mean to "crochet in the remaining loops" of your starting chain? The following pages feature photos and instructions that will help you understand these directions.