What skin are you using ? I can ' t think of one of them that would show fingerprints . You must have really greasy hands <| sep |> That is true . Can you suggest some books on strategy , some simple ones , not too advanced that deal with this problem . <| sep |> 4 k thats why <| sep |> Okay , will have a look . Thanks ! <| sep |> Other ' s have explained the difference , I ' ll try to explain why some programs don ' t have 64 bit versions . Regardless if it ' s 32 bit or 64 bit , the program still runs one instruction at the time . For 32 bit , each instruction is 32 bits long , and with 64 bits , hardly surprising , 64 bits . Now , 32 bits is plenty enough to describe all instructions the CPU can handle , so the remaining 32 bits in a 64 bit instruction is not really needed , but , because the CPU fetches data 64 bits at the time , that ' s a practical way to organize things . So , in short , a 64 bit program use more memory , theoretically but seldom in practice twice as much . If you have limited memory and you have , you don ' t want that . But , you might ask , isn ' t 64 bit better ? Well , it ' s quite a bit faster , in some use cases . It ' s good for stuff like graphics or intense number crunching , but most of the programs you use simply sit around thinking Is he going to press a key soon ? Is he going to press a key soon ? , and won ' t benefit from 64 bit . So , basically , in most cases , 32 bit will run just as fast and smooth as 64 bit , but will use much less memory .