What is normal distribution? - Definition from WhatIs.com


normal distribution

A normal distribution is an arrangement of a data set in which most values cluster in the middle of the range and the rest taper off symmetrically toward either extreme.

Height is one simple example of something that follows a normal distribution pattern: Most people are of average height, the numbers of people that are taller and shorter than average are fairly equal and a very small (and still roughly equivalent) number of people are either extremely tall or extremely short.

Here’s an example of a normal distribution curve:

normal curve

A graphical representation of a normal distribution is sometimes called a bell curve because of its flared shape. The precise shape can vary according to the distribution of the population but the peak is always in the middle and the curve is always symmetrical. In a normal distribution, the mean, mode and median are all the same.

Normal distribution curves are sometimes designed with a histogram inside the curve. The graphs are commonly used in mathematics, statistics and corporate data analytics.

Khan Academy provides an introduction to charting normal distributions:

This was last updated in November 2013
Contributor(s): Ivy Wigmore
Posted by: Margaret Rouse

Related Terms


  • structured data

    - Structured data contrasts with unstructured and semi-structured data. The three can be considered to exist on a continuum, with unstructured data being the least formatted and structured data being... (WhatIs.com)

  • spreadmart (spreadsheet data mart)

    - A spreadmart (spreadsheet data mart) is a situation in which a company's employees has inconsistent views of corporate data because each department relies on the data from their own spreadsheets. (SearchBusinessAnalytics.com)

  • user behavior analytics (UBA)

    - User behavior analytics (UBA) is a process in which security teams use monitoring tools to track, collect and assess the network activities of all individuals accessing those system to detect poten... (SearchSecurity.com)


  • Business intelligence - business analytics

    - Terms related to business intelligence, including definitions about business analytics and words and phrases about gathering, storing, analyzing and providing access to business data.

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question. Find an Answer.Powered by ITKnowledgeExchange.com

Ask An IT Question

Get answers from your peers on your most technical challenges

Ask Question

Tech TalkComment



    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.