The top program provides a dynamic real-time view of a running system. It can display system summary information as well as a list of tasks currently being managed by the Linux kernel. The types of system sum-
mary information shown and the types, order and size of information displayed for tasks are all user configurable and that configuration can be made persistent across restarts.

The program provides a limited interactive interface for process manipulation as well as a much more extensive interface for personal configuration — encompassing every aspect of its operation. And
while top is referred to throughout this document, you are free to name the program anything you wish. That new name, possibly an alias, will then be reflected on top’s display and used when reading and
writing a configuration file.

Htop is spin-off of top and much more visually appealing and extenisive in options.

Cheers
pavs