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# What's NGINX

**NGINX** is open source software for web serving, reverse proxying, caching, load balancing, media streaming, and more. It started out as a web server designed for maximum performance and stability. In addition to its HTTP server capabilities, NGINX can also function as a proxy server for email (IMAP, POP3, and SMTP) and a reverse proxy and load balancer for HTTP, TCP, and UDP servers.

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Originally **open sourced** in 2004 by Igor Sysoev
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It was written to solve the  "CK10" problem - 10.000 concurrent connections.
{% endtab %}

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NGINX Inc. founded to continue development and the creation of commercial offering: **NGINX Plus.** 
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### Use Cases

* High-performance web server: Used by 50% of the top 1.000 sites.
* Reverse Proxy: SSL/TLS Termination and content caching and compression.
* Load Balancer.


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