Browse Definitions:
Definition

thread

Contributor(s): Rene Martinez

1) On the Internet in Usenet newsgroups and similar forums, a thread is a sequence of responses to an initial message posting. This enables you to follow or join an individual discussion in a newsgroup from among the many that may be there. A thread is usually shown graphically as an inital message and successive messages "hung off" the original message. As a newsgroup user, you contribute to a thread by specifying a "Reference" topic as part of your message.

2) In computer programming, a thread is placeholder information associated with a single use of a program that can handle multiple concurrent users. From the program's point-of-view, a thread is the information needed to serve one individual user or a particular service request. If multiple users are using the program or concurrent requests from other programs occur, a thread is created and maintained for each of them. The thread allows a program to know which user is being served as the program alternately gets re-entered on behalf of different users. (One way thread information is kept by storing it in a special data area and putting the address of that data area in a register. The operating system always saves the contents of the register when the program is interrupted and restores it when it gives the program control again.)

A thread and a task are similar and are often confused. Most computers can only execute one program instruction at a time, but because they operate so fast, they appear to run many programs and serve many users simultaneously. The computer operating system gives each program a "turn" at running, then requires it to wait while another program gets a turn. Each of these programs is viewed by the operating system as a task for which certain resources are identified and kept track of. The operating system manages each application program in your PC system (spreadsheet, word processor, Web browser) as a separate task and lets you look at and control items on a task list. If the program initiates an I/O request, such as reading a file or writing to a printer, it creates a thread. The data kept as part of a thread allows a program to be reentered at the right place when the I/O operation completes. Meanwhile, other concurrent uses of the program are maintained on other threads. Most of today's operating systems provide support for both multitasking and multithreading. They also allow multithreading within program processes so that the system is saved the overhead of creating a new process for each thread.

The POSIX.4a C specification provides a set of application program interfaces that allow a programmer to include thread support in the program. Higher-level program development tools and application subsystems and middleware also offer thread management facilities. Languages that support object-oriented programming also accommodate and encourage multithreading in several ways. Java supports multithreading by including synchronization modifiers in the language syntax, by providing classes developed for multithreading that can be inherited by other classes, and by doing background "garbage collection" (recovering data areas that are no longer being used) for multiple threads.

This was last updated in September 2005 ???publishDate.suggestedBy???

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

-ADS BY GOOGLE

File Extensions and File Formats

SearchCompliance

  • smart contract

    A smart contract, also known as a cryptocontract, is a computer program that directly controls the transfer of digital currencies...

  • 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 ...

SearchCloudProvider

  • cloud ecosystem

    A cloud ecosystem is a complex system of interdependent components that all work together to enable cloud services.

  • cloud services

    Cloud services is an umbrella term that may refer to a variety of resources provided over the internet, or to professional ...

  • uncloud (de-cloud)

    The term uncloud describes the action or process of removing applications and data from a cloud computing platform.

SearchSecurity

  • cyberextortion

    Cyberextortion is a crime involving an attack or threat of an attack coupled with a demand for money or some other response in ...

  • Cybercrime

    Cybercrime is any criminal activity that involves a computer, networked device or a network.

  • National Security Agency (NSA)

    The National Security Agency is the official U.S. cryptologic organization of the United States Intelligence Community under the ...

SearchHealthIT

  • Practice Fusion

    Practice Fusion Inc. is a San Francisco-based company that developed a free electronic health record (EHR) system available to ...

  • RHIA (Registered Health Information Administrator)

    An RHIA, or registered health information administrator, is a certified professional who oversees the creation and use of patient...

  • 21st Century Cures Act

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

SearchDisasterRecovery

SearchStorage

  • storage medium (storage media)

    In computers, a storage medium is any technology -- including devices and materials -- used to place, keep and retrieve ...

  • Random Access Memory (RAM)

    Random Access Memory (RAM) is the hardware in a computing device where the operating system (OS), application programs and data ...

  • floating gate transistor (FGT)

    A floating gate transistor (FGT) is a complementary metal-oxide semiconductor (CMOS) technology capable of holding an electrical ...

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