Submitted by spec-indiahttp://www.spec-india.com
In a multi-user system or application, concurrency is a major issue that the development team must address. Concurrency, in the context of a software application, is the handling of multiple users attempting to access the same data at the same time.
For example, consider a multi-user order processing system that allows users to add and edit orders for customers. Adding orders is not a problem - since each new order generates a discrete record, several users can simultaneously add orders to the database without interfering with one another.