Latency vs. Bandwidth

The slow internet can be caused by low bandwidth or high latency.

Bandwidth (Speed): 

Bandwidth determines how fast data can be transferred over time.
Bandwidth is measured in Mbps or megabits per second.
download speed /upload speed

Latency: 

Latency is the delay. It’s the time it takes for your request for data to get to a server (like a website), and then for the data to get back to you.
Latency is measured in milliseconds, abbreviated “ms”.

e.g. 

Satellite Internet Connection (High Speed, High Latency): 

You would click a link on a web page and, after a noticeable delay, the web page would start downloading and show up almost all at once.

Theoretical Connection (Low Speed, Low Latency): 

You would click a link on a web page and the web page would start loading immediately. However, it would take a while to load completely and you would see images load one-by-one.

Cable Internet Connection (High Speed, Low Latency): 

You would click a link on a web page and the web page would appear almost immediately, downloading all at once.