Browse Definitions:
Definition

# recursion

Contributor(s): Lee Savidge

In computer programming, a recursion (noun, pronounced ree-KUHR-zhion) is programming that is recursive (adjective), and recursive has two related meanings:

1) A recursive procedure or routine is one that has the ability to call itself. This usually means that it has the capability to save the condition it was in or the particular process it is serving when it calls itself (otherwise, any variable values that have been developed in executing the code are overlaid by the next iteration or go-through). Typically, this is done by saving values in registers or data area stacks before calling itself or at the beginning of the sequence where it has just been reentered.

2) A recursive expression is a function, algorithm, or sequence of instructions (typically, an IF, THEN, ELSE sequence) that loops back to the beginning of itself until it detects that some condition has been satisfied. Here is a simple example (using a made-up computer source language):

```CODELINE1   N=0;
CODELINE2   IF N=<10 THEN DO WRITE LETTER;
CODELINE3   ELSE GOTO CODELINE6;
CODELINE4   N=N+1;
CODELINE5   GOTO CODELINE2;
CODELINE6   ...some other instruction
```

Here, the instructions labeled CODELINE2 through CODELINE5 are recursive until the condition of N having the value of 10. "IF N=<10" means "If N has a value less than 10." "N=N+1" means "Add 1 to the current value of N."

In mathematics, recursion has similar but more complicated meanings than it does when used in programming.

This was last updated in August 2005

#### Start the conversation

Send me notifications when other members comment.

Powered by:

## SearchCompliance

• ### risk map (risk heat map)

A risk map, also known as a risk heat map, is a data visualization tool for communicating specific risks an organization faces. A...

• ### internal audit (IA)

An internal audit (IA) is an organizational initiative to monitor and analyze its own business operations in order to determine ...

• ### pure risk (absolute risk)

Pure risk, also called absolute risk, is a category of threat that is beyond human control and has only one possible outcome if ...

## SearchSecurity

• ### federated identity management (FIM)

Federated identity management (FIM) is an arrangement that can be made among multiple enterprises to let subscribers use the same...

• ### cross-site scripting (XSS)

Cross-site scripting (XSS) is a type of injection security attack in which an attacker injects data, such as a malicious script, ...

• ### firewall

In computing, a firewall is software or firmware that enforces a set of rules about what data packets will be allowed to enter or...

## SearchHealthIT

• ### 21st Century Cures Act

The 21st Century Cures Act is a wide-ranging healthcare bill that funds medical research and development, medical device ...

• ### vendor neutral archive (VNA)

A vendor neutral archive (VNA) is a technology that stores medical images in a standard format and interface, making them ...

• ### HITECH (Health Information Technology for Economic and Clinical Health) Act of 2009

The HITECH (Health Information Technology for Economic and Clinical Health) Act of 2009 is legislation that was created to ...

## SearchDisasterRecovery

• ### crisis management plan (CMP)

A crisis management plan (CMP) is a document that outlines the processes an organization will use to respond to a critical ...

• ### business continuity and disaster recovery (BCDR)

Business continuity and disaster recovery (BCDR) are closely related practices that describe an organization's preparation for ...

• ### business continuity plan (BCP)

A business continuity plan (BCP) is a document that consists of the critical information an organization needs to continue ...

## SearchStorage

• ### all-flash array (AFA)

An all-flash array (AFA), also known as a solid-state storage disk system, is an external storage array that uses only flash ...

• ### volume manager

A volume manager is software within an operating system (OS) that controls capacity allocation for storage arrays.

• ### external storage device

An external storage device, also referred to as auxiliary storage and secondary storage, is a device that contains all the ...

## SearchSolidStateStorage

• ### hybrid hard disk drive (HDD)

A hybrid hard disk drive is an electromechanical spinning hard disk that contains some amount of NAND Flash memory.

Close