system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is the difference between bandwidth and download speed?
gpt
bandwidth is how much data can go through the pipe the way you're trying to use it.

trying to upload? your uploadspeed is your bandwidth

trying to download from a source providing the data at high enough speeds? your downloadspeed is your bandwidth

trying to download a huge file from your friends private homepage he's hosting on his old laptop in his room? your downloadspeed is lower than your actual bandwidth (because it's limited by his upload-bandwidth).