Have you ever browsed Windows Task Manager and wondered what some of its items are for? The Windows system processes section, located at the bottom of the list in Task Manager Windows 10, contains a number of processes that are important for the computer to run normally.
What do these processes do and what happens if you end them? Let's look at some of the most important items in Windows Task Manager.
Note: The new Task Manager in Windows 8.1 and later refers to most system items with easy-to-understand names, like Windows Logon Application instead of winlogon.exe. If you are using Windows 7, you will see the executable file name. In new versions of Windows, right-click a file and select Properties to see its executable name.
Important items in Task Manager
1. System (ntoskrnl.exe)
Windows will not let you remove the entry System confusingly named via Task Manager. That's because it's extremely important for the internals of the device. The system handles tasks at the kernel level, such as hosting drivers to ensure that the software can communicate with the hardware.
You can imagine the consequences if you stop this process. Because important drivers such as disk access and USB devices rely on System To do its job, closing this process locks the system and requires a hard reboot. If necessary reboot System (possibly when troubleshooting high CPU usage), you should restart your computer normally. Frequent problems with this entry may be a sign of a hardware problem.
2. Windows Logon Application (winlogon.exe)
You might think that this process isn't too important once you're logged into Windows, but quite the opposite. The first function of Windows Logon Application is to load the user profile when you log in. Any changes in the registry that you make to your account only take effect when you log in, thanks to this process.
Winlogon is also extremely important for security. Once you are logged in, this key combination will bring up the screen Windows Securitywhich has some quick links for you to change your password, sign out, and more.

But you can also enable an option called Secure sign-in that requires a tap Ctrl + Alt + Del when logging into Windows. Pressing this key combination ensures that you see the real Windows login screen and not a fake one designed to steal passwords.
To complete its task, winlogon also displays screensavers and/or locks the PC after not being used for a while. If you try to use command End Process on Task Manager, Windows will warn you that this is not a good idea.

If you try to do that anyway, your PC will go to a completely black screen with no hope of recovery. At this point, you will have to restart your computer for the process to run again.
3. Windows Start-Up Application (wininit.exe)
Wininit is a process that stabilizes Windows when you first log in and needs to remain active for the entire duration of use. The most important function of Windows Start-Up Application is to act as a springboard for most applications and background processes that run when you start Windows. This includes starting other important processes such as lsass.exe and lsm.exe.
Windows Start-Up Application run until you turn off the computer. Trying to end it too early will result in a Windows warning warning that you should not do this. And just like Winlogondoing so will cause the system to hang to the point where a reboot is required.
4. Client Server Runtime Process (csrss.exe)
As one of the essential Windows processes, the role of csrss has changed throughout the evolution of Windows. Previously, this process handled all of Windows' graphical elements. But now, it handles a few background functions instead.
The two most important roles of Client Server Runtime Process is to shut down Windows and launch the process conhost.exelaunch Command Prompt. It may not seem like much, but it's an important progress. If something goes wrong and the process doesn't run on startup, you'll get a blue screen error.
As you might guess, ignoring Windows' advice to end this process will result in the system freezing.
5. Windows Session Manager (smss.exe)
Another important part of the Windows boot process, Windows Session Manager has been available since Windows 3.1.
Whenever Windows loads, smss will take a few preparatory steps. It maps drives and creates virtual memory paging, etc. Once completed, it will invoke the winlogon process and you will see the login screen.
Clear, Session Manager persists after you log in. It monitors both winlogon and csrss waiting for either process to finish. If this happens as part of the standard process, Windows will shut down as usual. But if either process ends unexpectedly, smss will freeze the computer.

Like the processes above, attempting to end this process via Task Manager results in a warning and then causes the system to lock up.
6. Windows Shell Experience Host
This is a new process that works almost exclusively with the new elements of Windows 10. If you've used a previous version of Windows, you may have noticed the new changes Windows 10 makes to apps like clock and calendar. Progress Shell Experience Host handles these elements, along with the color and transparency effects of the Start menu or Taskbar.
In addition to the updated interface, this process also works to display Store apps in a window. If you use slideshow as wallpaper, you can thank it Shell Experience Host made it a reality. Unlike many other processes on this list, closing Shell Experience Host will not damage your system. Instead, Windows will restart it after a few seconds. But there's no reason to close Shell Experience Host because doing so will not change the look and feel of Windows.
7. Windows Explorer (explorer.exe)
This section handles the majority of the graphical interfaces you use every day. But what happens if you end up Windows Explorer in Task Manager?
As it turns out, terminating Windows Explorer will not only close any open File Explorer windows, but will also render the Start menu, Taskbar, and System Tray unusable.
However, restarting Explorer can actually help. If the Start menu or Taskbar starts acting up, a quick restart of the process may resolve the issues. It's much faster than restarting the PC because of a small issue limited to Windows Explorer.
In Windows 8.1 and later, you can right-click Windows Explorer and select Restart to finish and run again immediately. On Windows 7, you will have to right click on it and select End Processthen go to File > Run new task and enter explorer.exe for it to work again.
There are other ways to restart File Explorer if needed, so keep them in mind the next time you accidentally end a Windows Explorer task.

The processes that this article reviewed are certainly not the only important processes running in your Task Manager. But they're all important to your Windows experience in some way, and now you know what they do.
Thankfully, in most cases, Windows protects you from doing something stupid and accidentally shutting down an important process, so you don't have to worry much.