collectd is a small daemon which collects system information periodically and writes the results to an RRD-file.
What does collectd do? collectd collects information about the system it is running on and writes this information into special database files. These database files can then be used to generate graphs of the collected data. collectd itself does not generate graphs, it only collects the data. You should use software like drraw to generate pretty pictures from these RRD-files. Nonetheless, sample scripts are included to get you started on own graphing scripts.
