Spamming

hi,

i’m relatively new. sorry for asking what may be obvious to some of you.

i found out that i have been getting spam as part of the comments in my blog… so i changed the settings such that all comments need to be moderated.

however, what i’ve been reading in this support forum is that spamming can also be done through track-back? what is track-back and how do i know if my blog is being spammed through track-back. also, how do i prevent spam through track-back?

thanks!