Passing variables from HTML to PHP

Hi all. This might be a simple answer, but I'm still not sure what the case is. Okay, so I have a <form> in my html that has some <input>s. These each have a name and a value attribute to them, of course. I cannot seem to access the name/value pair in my php without using the $_POST method/variable names. Are you able to without $_POST? Example: ------------------- html: <input type="checkbox" name="foo" value="bar"> php: do this: echo "foo = " . $foo; // foo = bar or this: echo "foo = " . $_POST["foo"]; // foo = bar ------------------- So, should both of those php examples work the same? Thanks! ~Philip