Confusion about Spanning Tree

dppagc

How many spanning tree types are there?

1) 802.1d - common spanning tree
2) pvst - cisco proprietary
3) pvst+ - supports cisco and 802.1d
4) rapid pvst -has alternate and backup ports
5) MST
6) rapid-pvst+ - ??????

I am a little bit confused. Can anyone help me?

ninjaturtle

Score!! ---> http://packetlife.net/media/library/11/Spanning_Tree.pdf