Irons are important clubs used for hitting the ball from fairways, roughs, bunkers, and occasionally from tee boxes on shorter holes. They feature smaller clubheads than woods, and are angled to create lofted shots. Irons can be either cavity backed for a more forgiving shot, or have a solid "muscle back" requiring more accuracy in swinging. Irons are generally numbered as a way to distinguish between similar-looking clubs, with 1 being the longest iron and 9 the shortest. There are 4 broad classes of irons: long, medium, short and wedges.
Long irons are those numbered 1-4. While the 1 iron and 2 iron are increasingly rare, having been replaced by newer hybrid clubs, 3 and 4-irons remain standard clubs for most golfers. They are designed to hit the ball long distances with limited loft and are especially helpful when in the rough.
The medium irons are numbered 5-7. These are used for longer approach shots, typically between 130-200 yards. These clubs are generally seen as easier to use than long irons.
Your 8 and 9-irons are known as short irons. They produce less distance and more loft than long and medium irons. These clubs are especially helpful when obstacles or hazards need to be lofted over. They are also used for "bump and run" shots where golfers hit the ball from near the green with the intention of only lofting the ball a short distance before landing it on the green and continuing to roll towards the hole.
Wedges are similar to number irons but focus on achieving higher lofted shots. The pitching wedge, sometimes referred to as a 10-iron, is the most common wedge and used for shorter chipped shots. The sand wedge, designed to loft a ball out of sand bunkers, is the second most common wedge and producer a higher loft than pitching wedges. Other common wedges carried by some golfers are the gap wedge and lob wedge.