Key Difference: Apache refers to the 'Apache HTTP server'. It is an open-source, web server application designed for modern operating systems like Microsoft Windows, Netware, etc. Nginx ‘engine x’ is a free, open source HTTP and reverse proxy server. It is also an IMAP/POP3 proxy server. Unlike Apache, it is a lightweight server. Both are different in many other aspects too.

Apache refers to the Apache HTTP server. It is an open-source, web server application designed for modern operating systems like Microsoft Windows, Netware, etc. It is often described as a ‘heavy duty’ network server. It was developed by the Apache Software Foundation. This server provides a range of services like support to server side programming languages, etc. Performance of Apache is quiet the same as of a “high performance of other efficient web servers”. It provides support to authentication schemes. The facility of virtual hosting enables one apache server to serve different websites. Error messages are configurable in this server and it is supported by many graphical user interfaces.

Nginx ‘engine x’ is a free, open source HTTP and reverse proxy server. It is also an IMAP/POP3 proxy server. It was developed as a solution to the problem known as c10k in Apache; to handle a large number of requests simultaneously.  Originally, it is written by Igor Sysoev. It provides the basic HTTP server features like- serving of static and index files, modular architecture, SSL and TLS SNI support, etc. Some other HTTP server features include – name based and IP based virtual servers, flexible configuration, access log formats, fast log rotation, etc. Mail proxy server features include, SSL support, Authentication methods including POP3, IMAP and SMTP, etc. It is a lightweight web server and preferred over heavy Apache, if both are able to produced the desired result.

Both the servers can be combined to get the benefits of both.

Comparison between Apache and Nginx:

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