UD Code

Hi,

Anybody Can explain me what is d proper meaning of UD(Usage Decision) Code and wat iits effect in PM (where it use)....

also explain d meaning of catalog and wat effect it makes on PM.....hwz more it useful?

N d last 1 question

dat i want to doin certification IN *plant maintenance* from SAP so any1 expalin wat d procedure ffor doin certification from SAP n wats d minimum requ. fr doin dis?and also send d neceesary link for it..

Thanks,

Abhishek Vyas

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