Transfer and Distribution of Material Master Data 
Use
One of the first steps required for putting the R/3 System into operation is normally to transfer material data from a legacy system. This is because it is not normally possible to re-create the materials manually since there are so many of them.
If your system is a distributed system, it is also necessary to exchange data between these systems. Other scenarios making it necessary to distribute material master data are as follows:
Integration
You can transfer material master data from legacy systems in the following ways:
For a detailed description of direct input, the functions supported, and how to proceed, see the SAP library documentation CA Data Transfer Workbench
Transfer of Material Master Data (Industry) to the R/3 System.
For a detailed description of ALE, the functions supported, and how to proceed, see the following SAP library documentation:
BC ALE Introduction and Administration
BC ALE Quick Start
Creating Material Master Data
Sending Material Master Data
BC ALE Programming Guide
Master Data Distribution