a computer limits??

Hello have you ever noticed when playing littlechesspartner 1.10 or 12 that once you go to the settings there you can adjust the level by how many move's it can loook ahead. Course you have but here's something that been puzzling me what is it or any other computer that choses it's level's like this limit. For example If I told it to look 32ply would it play like Rybka or another powerhouse engine course not so how do you know chesspartner's limit's and what seprates them from eachother's version like 1.10,1.11,1.12 ??

the difference between versions can and often everything involving the software programming (level of play, internet reaction time ect, finding dubious moves on the lower settings..ect..) 

 of course not! humans make computers therefore computers are full of mistakes!