The conventional method of changing gear on a bike is by using control levers and mechanical cables. However, modern technology includes an electronic gear-shifting system. This technology involves switches connected by wire or wirelessly to a battery pack and to a small electric motor for switching the chain. Now the question pops up whether an upgrade is possible or buying an electric-geared bike is a feasible solution. If you want to upgrade your current to an electric version, you can do that only if you have 11-speed drivetrains. For other speeds, the upgrade may be possible but with more swapping of parts. You may confront issues with older frames though. So, consult an expert before doing so. On the other hand, buying a new model is anyways a fascinating choice.