You may have accidentally or unknowingly close a web browser tabs prematurely, which you may still need or want to view on. Most popular web browsers has built-in capability to reopen and recover recent closed tabs, instead of having you to dig through and search in browsing history, which could be a very long list, to recover those closed tabs.

One interesting point to note that almost all popular web browsers has a same common keyboard shortcut, or hotkey, to reopen the last and recently closed tabs. And the keyboard shortcut is:

In Windows: Control (Ctrl) + Shift + T
In Mac OS X: Command + Shift + T

The keyboard shortcut above does not work in Safari, which uses Command + Z hotkey to undo close tab.

By pressing the hotkey, one can immediately undo close tab and reopen the recently closed tabs. If you press the keyboard shortcut multiple times, it will continue to recover and reopen earlier closed tabs.

The reopen closed tabs keyboard shortcuts also useful and works in Microsoft Edge browser, which appears not having any command or button to reopen closed tabs in the GUI.