Similar to bulletin boards and forums. You may wish to avoid giving information to Web sites that have unacceptable policies or none at all. Most online companies let you use more than one screen name. You specify the type, model, manufacturer of a product and the service provides you with information about prices and where to buy the product. Some bots specialize in certain products.
Online companies try to limit spam because it annoys users and clogs the network.
You can help detour spam by using a different screen name when you enter chat rooms. Web sites of schools end in .edu. A network of computers, .net. And a military organization, .mil.