What is header? - Definition from WhatIs.com
Part of the Computing fundamentals glossary:

In information technology, a header is, in general, something that goes in front of something else and is usually repeated as a standard part of the units of something else. A header can consist of multiple field s, each containing its own value. Here are four common uses:

1) In a document , a header is some combination of text and image s that can be made to appear at the top of each page when displayed or printed.

2) In e-mail , the header is the part of a message that describes the originator, the addressee and other recipients, message priority level, and so forth.

3) In a computer file, a header may be a field that precedes the main file content and describes the length of the content or other characteristics of the file.

4) In a network transmission unit, a header precedes the data or control signals and describes something about the file or transmission unit, such as its length and whether there are other files or transmission units logically or physically associated with this one.

This was last updated in May 2005
Posted by: Margaret Rouse

Related Terms

Definitions

  • JBoss

    - JBoss is a division of Red Hat that provides support for the JBoss open source application server program and related middleware services marketed under the JBoss Enterprise Middleware brand. (WhatIs.com)

  • GPU supercomputer

    - A GPU supercomputer is a networked group of computers with multiple graphics processing units working as general-purpose GPUs (GPGPUs) in tandem on a single task. (WhatIs.com)

  • video card (graphics card)

    - A video adapter (alternate terms include graphics card, display adapter, video card, video board and almost any combination of the words in these terms) is an integrated circuit card in a computer ... (WhatIs.com)

Glossaries

  • Computing fundamentals

    - Terms related to computer fundamentals, including computer hardware definitions and words and phrases about software, operating systems, peripherals and troubleshooting.

  • 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

Share
Comments

    Results

    Contribute to the conversation

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