Agnostics - what do they believe?
An agnostic takes a more cautious line than the absolute belief of the atheist or the Christian. They believe that it is not possible to know if there is a creator god(s) or anything about them if there is!
Basically agnostics neither believe that there is a God nor believe that there isn't a God!
Read more: http://wiki.answers.com/Q/What_is_an_Agnostic#ixzz1jrHTWJMC
Dictionary definition of agnosticism
1. a. One who believes that it is impossible to know whether there is a God.
b. One who is skeptical about the existence of God but does not profess true atheism.
2. One who is doubtful or noncommittal about something.
http://www.thefreedictionary.com/atheism