Welcome to the offically-unofficial Android Launcher Thread.
A launcher is a piece of software that runs simultaneously with android to modify and/or enhance the user experience. Launchers can completely change the way android looks, feels, and operates. Luckily for us, there is a wide selection of well-developed android launchers available on Google Play.
A default launcher can been seen here on this Galaxy S3 phone. Many phones come with a launcher that looks similar to this.
The above picture is a very basic setup, consisting of apps and a few widgets. Basically any launcher will have apps and widgets, but we can manipulate them in various ways.
Here is a look at a phone with a free launcher modification designed to resemble a Windows Phone.
Certain launchers include features such as a scroll-able dock, gesture settings, custom lock-screens, themes, customized-widgets, and some other hidden goodies.
When you install a launcher on your phone, it's like starting your desktop fresh again. All your apps and data will still be on the phone, but you will need to make new shortcuts to your most-used stuff. This is an easy process and usually takes me less than 45 minutes.
Other images:
What launchers do you guys use, and which is your favorite?
Poll