What is c4f, c4b

The pattern I am knitting one of the rows says
K1 *p5, C4f, c4b repeat from * across

How do I do the c4f c4b?

Debbie

There should be an explanation in your pattern notes, just above the cast on instructions. C4F is cable 4 front - slip 2 st to a holding needle, let them flop to the front of the work, knit the next 2 off the L needle, then the 2 slipped sts off the holder. C4B is cable 4 back, same as above except the sts on the holder are held to the back of your work.