The remote can send an RF signal out (it is a different frequency than what X10 uses and not designed to control x10 directly). The RF that the remote sends out is received by the optional RF receiver which then converts the RF back into IR to control your equipment. This way you can take your remote about anywhere in your house and control equipment.
For your X10 you will still need an IR/RF converter to control the X10 devices.
Archer