You know mom, dad, sister, brother, aunt, uncle, and cousin, but then it gets complicated. Your cousins child is your cousin 1x removed, his child is your cousin 2x removed, then his child is 3x removed and so on. Your grandparents brother is your grand uncle, and his sister is your grand aunt. Their child is your cousin 1x removed and their child is your second cousin, his child is your second cousin 1x removed, and so on. Your great grand parents siblings are your great uncle/aunt their children are your first cousins 2x removed their children are your second cousins 1x removed, and their child is your third cousin. It keeps going on like this for a while. Hope this helped. :)
Your parent's Brother is your Uncle. Your parent's sister is your Aunt. Children of your Uncle or Aunt are cousins., Your cousin's children are your Second Cousins and their Children are your Third Cousins...Children of Third Cousins (and from there on out) are "Distant Cousins"