What Is a Web Server?
A web server stores and delivers the content for a website – such as text, images, video, and application data – to clients that request it. The most common type of client is a web browser, which requests data from your website when a user clicks on a link or downloads a document on a page displayed in the browser.
A web server communicates with a web browser using the Hypertext Transfer Protocol (HTTP). The content of most web pages is encoded in Hypertext Markup Language (HTML). The content can be static (for example, text and images) or dynamic (for example, a computed price or the list of items a customer has marked for purchase). To deliver dynamic content, most web servers support server‑side scripting languages to encode business logic into the communication. Commonly supported languages include Active Server Pages (ASP), Javascript, PHP, Python, and Ruby.
A web server might also cache content to speed delivery of commonly requested content. This process is also known as web acceleration.
Videos
Do Web Servers Need Public IP Addresses?
To be accessed by users outside its network, a web server needs a public IP address. To improve security, however, web servers are often “hidden” behind a proxy server or load balancer. Most large sites have multiple web servers, with load balancers to distribute traffic across them. It’s also possible for multiple websites to share the public IP address of a single web server, and the load balancer then uses information in the request URL to determine which site receives the client request.
Load Balancing and Web Servers
Load balancers improve performance and reliability by distributing the workload across multiple servers. When a load balancer is integrated into your infrastructure, a request first goes to the load balancer, which directs it to the correct backend server. In choosing a server, the load balancer first checks which servers are responding appropriately to requests. Then, it uses a preconfigured rule to select from among the pool of healthy servers.
