Here's the standard ranking for five-card poker hands. It should be second nature to you before you sit down at a poker table.
A straight (see below) that is also a flush (see below). Five cards of the same suit forming a five card sequence without gaps.
A straight flush with an ace on top is called Royal Straight, or just Royal.
Four cards of the same face value.
One three-of-a-kind combined with a pair.
Five cards of the same suit.
Five cards in a sequence without gaps.
Three of a kind
Three cards with the same face value.
One pair (see below) and then one more pair (see below) to go with it.
Two cards with the same face value.
If your hand has none of the above combinations, it will be compared according to its highest card.