How to use gears
There are many different bikes with different system and number of gears, in here we are going to talk about the most common.
1. City bikes with internal gear system.
This type of gears are so easy to ride.
You will use number 1 for up hill and the highest gear to run (7 or 8).
The maintenance on them is very easy since it is all covered from the dust and weather.
The advantage of it is that you can change gears without pedaling, meaning that if you stop suddenly you will be able to got to num 1 to start on a soft gear.
2. City bikes with external gear system.
When having the external gears system, is really important that the user makes the maintenance. If you use the bike everyday for commuting, you have to clean and lubricate the transmission twice a month minimum. On winter time, or if the bikes is always out side, you might have to do it more often.
On terms of using it, you have to understand how the gears work.
At the front, the small speed is for up hills and the big one to run.
At the back it works completely backwards, the small speed is to run and the big for up hills.
It is so important to understand it to don't get confused, to avoid annoying noises and to get the best of them.
Here you can see a clear image from "How to bike", on how you must and you mustn't use the gear system.