Availbility check 01 (Daily requirement) vs 02 (Individual Requirement) in SAP MM
01 and 02 are the checking group. Availability check is carried out with the help of these checking group and checking rule. Checking group 01 and 02 are maintained on the material master.
Individual requirement - For this system generates transfers the requirement for each order to the MRP .So that MM can either produce or procure.
Collective requirement- In this all the requirements in aday or in a wek are processed at a time. System stores all req and passes on to the MRP in MRP run.In this system performance is high however you can not do the backorder processing whereas in other you can do.