can any one explain client id to me?

i saw this on a site for mutlics

## Change you clientid (in hex) by default it is Generic
#NEWCAMD CLIENTID: 4343 # Mgcamd(6D67).newcs(6E73).Evocamd(6576).CCcam(4343) ...

what does it do?
is it worth using?

does it mean if i gave someone a nline, i could see if they put it in a box? or oscam? or multics?