Absolute

An absolute value is independent from the context in which it operates.

The notion of absolute has several usages:

• There are absolute names, also known as fully qualified name: \get_class(), new myClass()

• There are absolute path, which are path that starts at the root of the file system: /tmp/path/to/file.txt

• There are absolute values, supported by abs() math function

• The absolute parameter, when processing a DateTimeInterface difference

The notion of absolute is the opposite of the notion of relative, which depends on a local context.

<?php

// global namespace
namespace {
    // first definition
    function bar() {
        echo 'in the global scope.';
    }
}

namespace foo{
    // second definition
    function bar() {
        echo 'in the foo scope.';
    }

    bar(); // relative call: it goes to the second definition
    \bar(); // absolute call: it goes to the first definition
    \foo\bar(); // absolute call: it goes to the second definition
}

?>

Related : Fully Qualified Name, Absolute Value, Path, Relative, abs()