Definition of short-handed
The so-called short-handed poker tables are the 6-player tables. These are usually cash game tables. The short-handed variant is more popular in cash games, although there are some short-handed tournaments and sit 'n' goes. These tables will be more aggressive than regular full ring tables because you will be paying blinds more often. The ranges that will be played at these tables will also be larger. You will see more bluffing in shorthanded. Good poker players will prefer shorthanded because they can play more hands per hour than at full ring tables. Less experienced players will also make more mistakes at short-handed tables than at full ring.
Short-handed vs full ring
The debate is not new. Should you play shorthanded or full ring tables? If you're a tournament player, you won't have a choice since most tournaments are full ring. If you are a cash game player, it's up to you, it's a matter of style. You can make more money in shorthanded, but you will also have more variance. The variance is less in the full ring, so it's up to each player's style.