Some times you need to check how many packages are installed on your Linux box. This article will help you to find all installed packages on Redhat and Debian based Linux systems.
On CentOS, RedHat & Fedora Linux
Use one of following commands to list all installed packages on CentOS, RedHat & Fedora Linux systems
# rpm -qa
# yum list installed
On Ubuntu & Debian Linux
Use following command to list all installed packages on Ubuntu & Debian Linux systems.
# dpkg --get-selections