A Reverse Proxy is a server that sits in front of one or more web servers, intercepting requests from clients. This is different from a forward proxy, where the proxy sits in front of the clients. With a reverse proxy, when clients send requests to the origin server of a website, those requests are intercepted at the edge of the network by the reverse proxy server. The reverse proxy server will then send requests to and receive responses from the origin server. A reverse proxy sits in front of an origin server and ensures that no client ever communicates directly with that origin server.These reverse proxies are inserted to increase security, performance, and reliability.
Source: Cloudflare
Additional Reading: Small Cloud Configuration Mistakes Can Open Up Big Security Risks
Related Terms: Application Proxy