What is a flush cards?

Five cards of the same suit. For instance, if you have a 2, 5, 7, & Jack of diamonds, this would be known as a flush.

If you have a 2, 3, 4, 5, & 6 of spades, this would be known as a straight flush.

A royal flush (formally Royal Straight Flush) is the Ace, King, Queen, Jack, & 10 of the same suit.