How can I uninstall software?

GUI Methods

Ubuntu Software

The easiest way is to use Ubuntu Software (or Ubuntu Software Center in releases older than Ubuntu 16.04LTS). Open Ubuntu Software, click the Installed tab, select the app you wish to uninstall, and hit the Remove button.

Uninstall Apps using Software

Uninstall Apps using Software Center

Unity Dash (from Ubuntu 12.10, till 17.10)

Ubuntu 12.10 brought Unity 6, which introduced the Preview feature. So, from Ubuntu 12.10 onwards, you can just right click on (almost) any app icon on Unity Dash and click uninstall. Note that this won’t work on Ubuntu 18.04 LTS and above, as Unity was dropped and GNOME was made the new desktop.

Unity Dash
Uninstall Apps from Unity Dash

Synaptic

Synaptic is an advanced package management tool and gives you more control than other GUI methods like Ubuntu Software, Unity Dash, etc. It was infact the default app manager before Ubuntu 10.04. To install Synaptic, click here:
Install via Ubuntu Software

Or run this in Terminal:

sudo apt install synaptic

To uninstall apps through Synaptic, mark the packages to be removed and then hit the Apply button:

Uninstall Apps using Synaptic

Command Line Methods

These are for the command line fans out there. They’re pretty basic, but offers more advanced control and are lightweight.

apt

apt (newer and simplified apt-get) is the most commonly used command line tool for package management. Use the following command to uninstall any app:

sudo apt remove <app_name>

Remember to replace <app_name> with the package name of app you wish to uninstall.

aptitude

aptitude isn’t exactly a command line tool, as it has an interactive ncurses based GUI. However, the following command can be used:

sudo aptitude remove <app_name>

snap

Ubuntu 16.04LTS and newer has support for snap packages, but can be installed on Ubuntu 14.04LTS too via updates. To uninstall a snap app, try:

snap remove <app_name>

and if that doesn’t work:

sudo snap remove <app_name>

Note that all the above methods will work only on apps installed normally, i.e through package management (Ubuntu Software, Synaptic, apt, snap, etc.) and not on softwares manually installed using some root scripts or by directly copying to home. Though the above methods look very different, all of them use the same APT or Snappy package manager backend underneath. There are many more methods for installing/uninstalling apps, but the ones involving APT or Snappy are the recommended and most popular methods.