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+# Shebang
+A shebang is a special line at the top of scripts that start with the character sequence `#!` followed
+by a path to an interpreter, optionally followed by any arguments meant to be supplied to it. It was
+first used in [Unix](unix.md). The function of a shebang is to allow an arbitrary script written in
+any [programming language](programming_language) with the executable bit set to be executed as a
+native executable. The first character (`#`) is usually a comment in most scripting languages -- and
+languages that don't use it for comments commonly support the shebang as an special case, like [Lua](lua.md).
+
+When a script with a shebang is executed, the [kernel](kernel.md) interprets the line and tries to execute
+the interpreter specified in the line; if it succeeds then the kernel forwards the script to be actually executed by
+that interpreter.
+
+A common shebang is `#!/bin/sh`, which is used in [shell scripts](shell_script.md) (here for a [POSIX](posix.md) sh).
+Because the path has to be absolute, this create problems for interpreters that may not be in a standard path,
+so for other languages, `env` is actually called to resolve the actual path of the interpreter. For example,
+`#!/usr/bin/env python3` will attempt to search for the actual path of the [Python](python.md) interpreter.