La in-dirección es una técnica de programación. El concepto se basa en hacer referencia indirecta a los datos usando las direcciones de memoria que los contienen o mediante punteros que señalan hacia esos datos o a las direcciones que los contienen. En la memoria no sólo se almacenan datos de los programas (como letras, caracteres gráficos, números naturales, números enteros, coma flotante, etc.) sino también direcciones de memoria, que al fin y al cabo también son datos. Para efectos de almacenamiento y manipulación por el microprocesador, todos estos datos no son más que una secuencia de bytes en diferentes celdas. El que una secuencia de bits determinada se intérprete como un número o como una dirección depende del programador. El mecanismo de in-dirección se puede encadenar de manera arbitrariamente larga. La dirección que contiene la dirección de un dato, a su vez se puede almacenar de nuevo en memoria. Es posible almacenar las direcciones de tal forma que haya que seguir un encadenamiento de in-direcciones para llegar finalmente a acceder al dato. En el siguiente ejemplo, la "celda" (dirección de memoria 0x00000100) contiene el dato 0x00000200 que a su vez representa la dirección de la nueva "celda" que contiene el dato que corresponde a una dirección que contiene un dato que representa la dirección 0x00000400 que finalmente contiene el dato que nos interesa. Y así podemos definir a voluntad o conveniencia los diferentes niveles de in-dirección que necesitemos.

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In computer programming, indirection is the ability to reference something using a name, reference, or container instead of the value itself. The most common form of indirection is the act of manipulating a value through its memory address. For example, accessing a variable through the use of a pointer. A stored pointer that exists to provide a reference to an object by double indirection is called an indirection node. In some older computer architectures, indirect words supported a variety of more-or-less complicated addressing modes. A famous aphorism of David Wheeler goes: "All problems in computer science can be solved by another level of indirection" (the "fundamental theorem of software engineering").This is often deliberately mis-quoted with "abstraction layer" substituted for "level of indirection". Kevlin Henney's corollary to this is, "...except for the problem of too many layers of indirection." Humorous Internet memorandum insists that: (6) It is easier to move a problem around (for example, by moving the problem to a different part of the overall network architecture) than it is to solve it. (6a) (corollary). It is always possible to add another level of indirection. Object-oriented programming makes use of indirection extensively, a simple example being dynamic dispatch. Higher-level examples of indirection are the design patterns of the proxy and the proxy server. Delegation is another classic example of an indirection pattern. In strongly typed interpreted languages with dynamic datatypes, most variable references require a level of indirection: first the type of the variable is checked for safety, and then the pointer to the actual value is dereferenced and acted on. Recursive data types are usually implemented using indirection because otherwise if a value of a datatype can contain the entirety of another value of the same datatype, there is no limit to the size a value of this datatype could need. When doing symbolic programming from a formal mathematical specification the use of indirection can be quite helpful. To start with a simple example the variables x, y and z in an equation such as can refer to any number. One could imagine objects for various numbers and then x, y and z could point to the specific numbers being used for a particular problem. The simple example has its limitation as there are infinitely many real numbers. In various other parts of symbolic programming there are only so many symbols. So to move on to a more significant example, in logic the formula α can refer to any formula, so it could be β, γ, δ, ... or η→π, ς ∨ σ,.... When set-builder notation is employed the statement Δ={α} means the set of all formulae — so although the reference is to α there are two levels of indirection here, the first to the set of all α and then the second to a specific formula for each occurrence of α in the set Δ.

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