Variables in PHP are represented by a dollar sign followed by the variable name. The variable name is case-sensitive.
Variable names follow the same rules as other labels in PHP. (…)
The setcookie() function defines a cookie to be sent along with the rest of the HTTP headers. Due to RFC requirements cookies, like all headers, must be sent before any output from your script. (…)
PHP has a built in set of mail functions that allow a properly coded script to send email. This can come in handy when dealing with information submission forms, shopping carts, etc. (…)
