R1

History
The playstation 1,2 and 3 all have the button R1. On the playstation 1 and the playstation 2 the R1 button was pressed down like any other button but on the playstation 3 controler the R1 and L1 button hang over the edge of the controller. On the playstation 1 the R1 button wasn't used much and the same was with the playstation 2 but on the playstation 3 that all changed here are some uses for the R1 button.

Little big planet
On little big planet the R1 button is used to grab hold of certain materials like sponge on the second level on little big planet you learn how to use grabbing to your advantage.

Call of duty
On call of duty (cod) the R1 button is used to shoot.

Right 1
R1 stands for Right 1 because it is on the right of the controler R2 is behind it and R3 is the right anolog stick being pushed down.