In billiards the pool cue is used to strike a ball, usually the cue ball.
Cues may come in multiple pieces to make them easier to transport. A typical pool cue will be about 60" long, and weigh 18-21oz. A cue is made up of a butt, a shaft and ferule, and a tip. The butt can be ornate with inlays, or very plain. The shaft is made from a hard wood such as maple. The ferule holds the tip. Good tips are made from compressed leather and can take a lot of abuse. Cheap cues have replacement tips that slide onto the shaft, and often lose their shape quickly.
The important factor when picking a cue is that it feels balanced to you and the weight and length give you confidence at the table. An Irish linen wrap on the pool cue will give you a nice grip, and absorbs moisture from your hand. Irish Linen historically came from fishing line manufacturers in Ireland.
There have been a number of famous cue makers over the years. The most famous are Herman J Rambow, and George Balabushka. Their cues are very valuable to collectors. Unlike most collectible cues, their cues are valued because of how well they worked as a pool cue. Rambow is considered to be the person to have perfected the jointed cue.