What is ADM methodology? how it will related to SAP R/3 system?

hello friends,

What is ADM methodology? whoes product it is? and how can we use it to SAP R/3 system (for implementation or support).

What is the main difference between ASAP and ADM methodology.

Can anyone have an knowledge on ADM methodology? Pls send the information or document to email: collectorsrin@yahoo.com.

thanks in advance,

will be rewarded,