The Windows Event Viewer shows a log of application and system messages, including errors, information messages, and warnings. It’s a useful tool for troubleshooting all kinds of different Windows problems.

Events are placed in different categories, each of which is related to a log that Windows keeps on events regarding that category. While there are a lot of categories, the vast amount of troubleshooting you might want to do pertains to three of them:
Application: The Application log records events related to Windows system components, such as drivers and built-in interface elements.
System: The System log records events related to programs installed on the system.
Security: When security logging is enabled (it’s off by default in Windows), this log records events related to security, such as logon attempts and resource access.

Double click on the log to view more details like event ID etc.

To save log files:
To generate these logs, please follow the steps listed below:
1.Open “Event Viewer” by clicking the “Start” button
2.Click “Control Panel” > “System and Security” > “Administrative Tools”, and then double-click “Event Viewer”
3.Click to expand “Windows Logs” in the left pane, and then select “Application”.
4.Click the “Action” menu and select “Save All Events As”.
5.Name the file “eventviewer.evtx” and click the “Save” button.
6.Click the “OK” button if you see a “Display Information” dialog.