Explanation
The dpkg command is used to manage Debian packages on Linux systems. The -r option removes a package but leaves its configuration files in case the package is re-installed. The -P option purges a package and removes its configuration files as well. The -s option shows the status of a package and the -L option lists the files installed by a package. References:
* LPI Linux Essentials, Chapter 6: Managing Software, Section 6.2: Debian Package Management
* LPI Linux Administrator, Exam 101: System Architecture, Topic 102: Linux Installation and Package Management, Objective 102.5: Manage shared libraries
* LPI Linux Engineer, Exam 201: Linux Kernel, Topic 201: System Architecture, Objective 201.1: Kernel Components and Compilation