Bandwith quota is unclear

If I edit a package it says

Bandwidth: 10000 MB

by default.


Maybe it's obvious for Linux savvy users what this quota is, but for me it's not:

- Is it the general I/O bandwith in MB/s? (I think it's that, but then it should read I/O Bandwith and MB/s (maybe add an info button that tells that when hovered with the mouse behind for stupid users like me.)
- Is it a montly traffic limit?
- S.th. else?


I'd be thrilled, if you could tell me where the script related to that setting is, so I could learn more about Linux by reading it's commands, but it's not really important :-)