[grayfaced]

You're probably not running either unless you know what they are. Top is an equivalent of windows taskmanager, most often to used identify "top" processes using memory/cpu (and other resources) and only ran briefly. Atop is a different long-running version used to create logs of the same data to understand trends.

[cesarb]

> [...] and only ran briefly. Atop is a different long-running version used to create logs of the same data to understand trends.

atop is also normally only ran briefly. It has an optional mode (enabled by default in some, but not all distributions) in which it runs as a service and saves a snapshot of the system state every few seconds; atop can read and show these snapshots when ran briefly.