Manuals

 Brainfuck
 Turing 2bit

An Eight-Instruction Turing-Complete
Programming Language

Brainfuck is the ungodly creation of Urban Müller, whose goal was apparently to create a Turing-complete language for which he could write the smallest compiler ever, for the Amiga OS 2.0. His compiler was 240 bytes in size.

The Language

A Brainfuck program has an implicit byte pointer, called "the pointer", which is free to move around within an array of 30000 bytes, initially all set to zero. The pointer itself is initialized to point to the beginning of this array.

The Brainfuck programming language consists of eight commands, each of which is represented as a single character.

>	Increment the pointer.
<	Decrement the pointer.
+	Increment the byte at the pointer.
-	Decrement the byte at the pointer.
.	Output the byte at the pointer.
,	Input a byte and store it in the byte at the pointer.
[	Jump past the matching ] if the byte at the pointer is zero.
]	Jump to the matching [.

The semantics of the Brainfuck commands can also be succinctly expressed in terms of C, as follows (assuming that p has been previously defined as a char*):

>	becomes	++p;
<	becomes	--p;
+	becomes	++*p;
-	becomes	--*p;
.	becomes	putchar(*p);
,	becomes	*p = getchar();
[	becomes	while (*p) {
]	becomes	}

Source: Brian Raiters, Muppetlabs