Easy! IT | IT Term | Daemon
This article is a rough explanation of Daemon.
Everything might be not exactly correct in this article but it’s beneficial for beginners to understand IT terms. If you want to learn IT but don’t have any experience working in the IT industry, I hope it helps you understand IT. And I hope that this article motivates you to study IT more.
Let’s start our 3 minutes lesson!
What is Daemon?
A daemon is a computer program that runs as a background process.
- A daemon is usually the resident program.
- A daemon is not a demon, it’s in the talk about multitasking computer operating systems(Unix, Linux).
- A daemon is waiting for its tasks on the memory.
1. What is OS?
In the human world, OS would be a nationality or personality. Each OS has each language and each function. And Linux is one of the OS software. So, if someone tells you this server is Linux, you can imagine what kind of language you need to talk with it and what it can do.
If there are any OS software systems, a laptop can’t do anything. It’s the same with smartphones or other server devices.
In other words, the device can be any OS system if you install them with that device.
2. What is a Resident program?
A resident program which is also called a resident module is staying in memory throughout the lifetime of a computing session such as an anti-virus program.
Resident programs are always ready for their work, and they always stay where they can work. They never have a day off if the computer is on. They are always required to get their guard up. ( Though it could be that they are just ready sometimes, not work.)
A daemon is one of these resident programs.
3. What is a daemon program?
A daemon is an alias in Unix-like OS worlds.
If you know WindowsOS, please think about it like a daemon is a service on Windows. Services are just waiting for their work in the memory before they get work, and they are back to ready after they finish their work.
A daemon is called a background process, it means they work hiding in the mirror world. You can’t see they work in your world.
Daemon has a unique name rule. Most of daemon has “d” after their names, such as crond, httpd, ftpd and so on(List of Unix daemons – Wikipedia).
I hope that you understand “Daemon”. Maybe it’s not easy to imagine first. Have you ever received “MAILER-DAEMON”? It’s the error mail from the mail server. It occurs when sender email addresses don’t exist or those email addresses are wrong. This bounce message is sender by a daemon. After this daemon receives an email and he founds that it doesn’t exist, he tells you that “Sorry, nobody has that address”. He doesn’t mean he annoies you but he wants to support you to send the message to the right person. Even if you receive this message, please don’t be mad or upset. Just check that email address again!
fin
