As a web developer, you probably know that you always need to use a testing environment to run your web application or to test a new feature to be added to your current application without messing out with your current on server running application.
Every Geek knows that there is no place like 127.0.0.1 which is your local computer, so get the power of your computer and start your testing environment weather you are a PHP, Java Or even Ruby developer you can use one of the following list of top 6 free localhost web servers I’ve been using in the past few years.

1- XAMPP

Download from: www.apachefriends.org

Many people know from their own experience that it’s not easy to install an Apache web server and it gets harder if you want to add MySQL, PHP and Perl.
XAMPP is an easy to install Apache distribution containing MySQL, PHP and Perl. XAMPP is really very easy to install and to use – just download, extract and start.

2- Nginx

Download from: www.nginx.org

Nginx is one of a handful of servers written to address the C10K problem. Unlike traditional servers, Nginx doesn’t rely on threads to handle requests. Instead it uses a much more scalable event-driven (asynchronous) architecture. This architecture uses small, but more importantly, predictable amounts of memory under load.
Even if you don’t expect to handle thousands of simultaneous requests, you can still benefit from Nginx’s high-performance and small memory footprint. Nginx scales in all directions: from the smallest VPS all the way up to clusters of servers.

3- Roxen

Download from: www.roxen.com
Roxen WebServer is a full-featured open-source web server distributed under the GPL license. It runs on a number of different operating systems including Windows, Linux, Solaris and Mac OS X.

4- Apache

Download from: www.apache.org
The Apache HTTP Server Project is an effort to develop and maintain an open-source HTTP server for modern operating systems including UNIX and Windows NT. The goal of this project is to provide a secure, efficient and extensible server that provides HTTP services in sync with the current HTTP standards.
Apache httpd has been the most popular web server on the Internet since April 1996, and celebrated its 15th birthday as a project this February. The Apache HTTP Server (“httpd”) is a project of The Apache Software Foundation.

5- Tornado

Download from: www.tornadoweb.org
Tornado is an open source version of the scalable, non-blocking web server and tools that power FriendFeed. The FriendFeed application is written using a web framework that looks a bit like web.py or Google’s webapp, but with additional tools and optimizations to take advantage of the underlying non-blocking infrastructure.

6- Lighttpd

Download from: www.lighttpd.net
Security, speed, compliance, and flexibility — all of these describe lighttpd (pron. lighty) which is rapidly redefining efficiency of a webserver; as it is designed and optimized for high performance environments. With a small memory footprint compared to other web-servers, effective management of the cpu-load, and advanced feature set (FastCGI, SCGI, Auth, Output-Compression, URL-Rewriting and many more) lighttpd is the perfect solution for every server that is suffering load problems. And best of all it’s Open Source licensed under the revised BSD license.

Conclusion

There are more than 100+ webservers applications that you can download and give them a try. but those 6 free open source high-performance http servers are based on my experience in using them. the oldest one i use is the XAMPP and i still use it till now. If you would like to recommend another software please name it on a comment below… Have a great day everybody…