That last sentence is starting to sound suspiciously like homework :-) Any web-based application is going to be inherently multi-threaded - HTTP requests can come in at any moment, whether the previous HTTP request is still processing or not. Each HTTP request handler is, in effect, a separate thread. This is why any language used for web-based applications needs to have good support for mutexes/monitors/whatever, which is why PHP is such a crummy language - no decent support for locks.
I need to work it out in a web application in visual basic (vb).
Please give brief details about this concept and example, such as the importance of threading and how to use.