Eclipse is an open source community whose projects are focused on building an open development platform comprised of extensible frameworks, tools and runtimes for building, deploying and managing software across the lifecycle. Eclipse has a huge support community consisting of major technology vendors, innovative start-ups, universities, research institutions and individuals extend, complement and support the Eclipse platform.  

I have been a professional PHP programmer for 3 years and this remains my central tool for developing PHP.  While eclipse was created to develop java the extensive support allows this IDE/platform to be used simply for everything.  I highly recommend this software for simple or complex projects.  Plus its completely free to use 

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