Basics:

The difference of Woods vs. Irons:
* Woods hit the ball farther then irons.
* Irons hit the ball higher.
* You choose a wood (1w) usually off the Tee for par 4 and 5's and in the fairway (3w) when you cannot reach the green and are farther then your longest drive away.
* Use Irons on some par 3's (if you are close enough). You may use a wood if you are farther then you longest iron.
* Always use a mid-lofted iron from deep rough (6i or 7i).
* You may use your most lofted wood (5w-7w) from standard rough.

The difference in Irons:
* The higher the number, the more lofted the club.
* The more loft, the higher the ball will go, but shorter in distance.
* The Sand Wedge is the most lofted (unless you carry a Lofted Wedge). This is used out of the, you guessed it, the sand. But also from shorter distances.

The differences in Woods:
* The higher the number the more lofted the club.
* The more loft, the higher the ball will go, but shorter in distance.
* The driver (1w) is the longest club. This should only be used from the tee box and on a tee.
* The 3w is longest club you will use after any tee shot.
* Why is there no 2w? Well, there are, but these days, a spoon (as it was called in the days) is completly extinct. They make "strong" 3 woods now that will make the ball go farther then a standard 3w.

Again, just the basics. I could talk (as well as everyone on this site) about when to use each club, how to use it, why it does what does when you do it, and that will be WAY to much information for you.

My suggestion for beginners is this: Carry the following in you bag:

3W, 5W, 5I, 7I, PW, SW and Putter. That's it...oh, and a lot of balls.

No driver. Not until you hit the 3w consistantly. No 1,2,3,4 irons either. The 5i will give you plenty of loft from the fairway and get the ball going just fine. Once you simplify the choices and hit the club often enough, you will want to branch out a little and need the rest. But until then. Master these on the range and the course and you will be all the better off not worrying about what club to hit.