Most (well written) PHP programs recognize GET from POST requests and handle them appropriate. However most of them are not aware of HEAD requests and handle them identical to GET. This is a waste of resources and is in contravention to HTTP 1.1 protocol (RFC 2616).

While programming in PHP often you will find that a simple echo or log statement is not sufficient. You have found out where a problem is happening but you have no clue why it is executing that code in the first place. This is where execution path comes in handy. With a simple call you can display the whole execution path of the code so far, every function that was executed, in which file and in which line number. Isn't that handy?