CSGO currently runs on 64-tick servers, meaning that all of the action on a players screen might not really match what the server says it is. A faster server takes more snapshots of whats going on in game compared to slower ones, and thats why CSGOs player base wants those faster servers.

Is CSGO matchmaking 64-tick?

While the main CS:GO matchmaking runs on 64-tick, many competitive competition takes place on servers running 128-tick.

Do 64-tick smokes work on 128 tick servers?

Because of the tickrate, the release of the grenade will have different speeds on 64 and 128 tick. In the video below, you can see that the release happens at slightly different heights on the two tickrates. Using the jumpthrow bind will give you the same result every time, if your playing on the same tickrate.