[PHP] Cheat sheet, part 1 - basics

I know there are dozens of similar stuff on net, but none would be as good for me as one made by myself. Created while reading (mainly) a brick called PHP and MySQL Web Development: Vademecum.

[PHP] quick start

PHP: Hypertext Preprocessor is a widely used, general-purpose scripting language that was originally designed for web development to produce dynamic web pages. For this purpose, PHP code is embedded into the HTML source document and interpreted by a web server with a PHP processor module, which generates the web page document - but it doesn't mean you can't view .php sites offline.