How to uninstall a program through the App Store?
No.

You cannot uninstall apps from within the App Store.

How can I delete an application?


You can delete them like in iOS:


Open Launchpad.
Click and hold the app you want to delete (or hold &#x2325;)
Delete by clicking on the X.


Note: The X appears only for apps which have been installed using the Mac App Store.
Locate the Applications folder where the app is located:


/Applications or /Users/my_name/Applications
Drag the application to the Trash.


Note: This will only remove the application - this will not remove some other files which may be related to the app (e.g. preferences). If you want to remove such files as well, you can use tools like AppCleaner which @james.garriss has mentioned. 


Besides this, applications which have not been installed via the Mac App Store sometimes provide their own uninstaller in the installer .dmg image. I usually keep them in a folder Applications/Uninstaller which I created.