I installed an app but I don't know how to run it. Help?

The usual way of launching a program in Ubuntu is to press the 'windows' key to pull up the dash, then start typing the name of the program. A clickable icon should be displayed below.

However, sometimes it can be difficult to find an application in the menus or the dash. Fortunately, there are ways to find it from a command line even when it doesn't show up in the GUI. First, try to determine the actual package name by searching the local package list for the application name:

• dpkg -l | grep -i appname
  (replace 'appname' with your application name)

Then, once you have the package name, tell the system to print out its launcher command:

• cat $(dpkg -L pkgname | grep '\.desktop$') | grep ^Exec
  (replace 'pkgname' with the package name from the previous step)

This should give you one or more lines of output which all start with Exec=. Simply copy the command after the '=' and paste it into a terminal, and your application should start up.

Here is an example session:

user @ host> dpkg -l | grep -i bastion
ii  bastion      1.3-0ubuntu1      Experience that redefines storytelling in games

user @ host> cat $(dpkg -L bastion | grep '\.desktop$') | grep ^Exec
Exec=/opt/bastion/Bastion/bastion64.sh

user @ host> /opt/bastion/Bastion/bastion64.sh

Depending on the package, it may also care which directory it is run from. You may need to extract the path data from the desktop file too:

• cat $(dpkg -L pkgname | grep '\.desktop$') | grep ^Path
  Path=/opt/packagename/bin
  (replace 'pkgname' with the package name from the previous step)

Then just cd to the directory after 'Path=', and run the command from the 'Exec=' line. This is normally not necessary, but can be helpful in some cases.