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Ali Azhar
Last Updated February 21, 2022 12:17 pm

A thread is a sequential, connected, related set of data or content elements found in social media, online messaging, and computer programming settings.

What is a thread in social media?

On social media platforms (Facebook, Twitter, Reddit, etc.), a thread is a series of replies to a single post. They can be from the original post’s author or from other users, but they are all connected and can be viewed from the original post. A common instance of a thread, for example, is when a Twitter user posts multiple replies to the same main tweet to share longer thoughts or break up parts of a story for dramatic effect.

What is a thread in messaging?

In text messaging, emailing, and other forms of private online communication, a thread is a way of grouping messages pertaining to the same conversation. An example of this is when a group of emails are organized in a way that allows each message to appear individually instead of duplicating the entire message chain that preceded it. Similar threads appear in online messaging platforms such as Slack or Apple’s iMessage, where a user can create a new thread by responding to another user’s message.

What is a thread in programming?

In programming, a thread is a part of a program that can execute independently of other parts. This is the smallest sequence of instructions that can be managed independently by a scheduler within a broader operating system. Multiple threads can exist in a single process and share computer resources, whereas multiple processes do not share the same resources. Operating systems that support multithreading enable programmers to design programs with threaded parts that can execute concurrently. Single-threaded operating systems, on the other hand, process one command at a time.

What is a Thread in an Operating System

The main advantage of threading in an operating system serring is that they can simplify multiple processes running simultaneously in an application. For the browser in an operating system, the main thread processes user events and updates all users. The browser uses a single thread for all JavaScript applications on a webpage. It can also be used to perform reflows, garbage collection, and layout.

When operating system browsers were initially developed, they were designed to support a single process at a time. With the development of threads and processes, browsers are able to offer multiple tabs. 

When a request is made in a web browser, a process is initiated that may create several threads to make the task easier. In some cases, the process can trigger the operating system to start another process, which might also have a series of threads.

It can be easy to confuse multi-threading with multitasking. While multitasking refers to doing many tasks at the same time, multi-threading refers to the ability to process multiple threads at the same time. 

Microsoft Word is an example of multi-threading in operating systems. MS Word can save files, check spelling, change fonts, read files from a hard drive, and perform several other tasks simultaneously. No additional resources from the OS are required for threading. If a thread gets blocked, the process can initiate a new thread to execute the user request. Threads in the operating system can also share files and processes and access data of other threads.

Types of OS Threads

There are two main types of threads in operating systems—user-level and kernel-level.

User Level

Threads that are implemented by the users are known as user-level threads, which are smaller and faster than kernel-level threads. They consist of a program counter, registers, a small process control block, and a stack

The advantage of user-level threads is that they are easier to create and manage than kernel-level threads. There is no need for kernel-level privileges when thread switching in user-level threads.

Kernel Level 

Kernel-level threads are handled directly by the operating system with all the thread management done by the kernel. The advantage of kernel-level threads is that they can be used to schedule multiple threads of the same process on different processors. They also allow for multi-threading, and if a kernel-level thread is blocked, another thread for the same process can be scheduled by the kernel.