Remember, the Delegation Model for a Web server is very simple. When a request is sent to a Web server, it simply passes the request to a program that can handle the request well. A Web server simply provides an environment in which server-side programs can be executed and responses returned, not beyond the scope of functionality. Server-side programs typically have transaction processing, Database connectivity, and messaging capabilities.
Although Web servers do not support transaction processing or database connection pooling, they can employ various strategies to achieve fault tolerance and scalability, such as Load balancing, The buffer (caching). Clustering – features are often mistaken for features exclusive to application servers.
Simple to understand
The basic function of Web server is to provide Web information browsing service. It only needs to support HTTP, HTML document formats, and urls. Works with the client’s web browser. Because the primary protocol supported by Web servers is HTTP, HTTP servers and Web servers are usually equal