If you are using the Details view for files and folders in File Explorer, you can change the width of all columns to fit their contents. This will improve your productivity and save a lot of time when you have to deal with columns and tables.
First of all, open File Explorer. Click the View tab of the Ribbon, and enable the "Details" view:
Alternatively, you can right click the column title bar row. In the context menu of the column title bar, you will find a couple of commands.
Tip: You can add Size All Columns To Fit to the context Menu In Windows 10. If you are using the Details view for files and folders in File Explorer, this will improve your productivity and save a lot of time when you have to deal with columns and tables.
Finally, you can use a secret keyboard shortcut. Click on any file or folder and press Ctrl + + hotkeys (Ctrl and the plus key) on your keyboard. All columns will be resized to fit!
Note that you may have to press the '+' key on the numeric keypad of your keyboard. If you have a keyboard without a dedicated numeric keypad as some laptops have, then you may need to use the Fn key along with Ctrl to input the '+' key correctly. The + key on the key with the 'equals to' sign (=) does not work for this trick.
This handy trick works in many places and apps in Windows. It is applicable to Windows Explorer in Windows XP as well.
For example, you can use it in the Registry Editor app to resize the columns in the right pane.
The "Details" tab of the Task Manager comes with a grid which also can be resized using the mentioned key sequence. Note: In Windows 10, there is a new Task Manager app, which allows you to copy process details and has new useful features like startup impact calculation. While in the old, classic Task Manager you were able to resize columns in the same manner on any tab using this Ctrl++ key combination, the new Task Manager only allows you to use this on the Details tab. On other tabs, Microsoft has implemented the ability to show the data as a hierarchical list, i.e. "treeview". That treeview is a completely different control, so it does not allow you to use this keyboard shortcut.
If you are not happy with the new Task Manager, get the old one back using this tutorial: How to restore the good old Task Manager in Windows 10.