Quick Summary:
There are four (4) general means for a rigger to control a vehicle/drone.
4) Autopilot. You send a command (usually over the matrix) and order your drone's dog-brain (or agent if you installed one) to complete an action to the best of its ability.
3) Manual. This normally refers to Vehicles only. This refers to taking the physical controls and operating them, like steering wheel for cars etc. Use that meat-body to operate that heavy machinery! Suffice to say, this does NOT require a commlink OR an RCC, but is unlikely to be possible for most drones. Most.
2) Remote. This refers to operating the vehicle or drone…. remotely. You use the Matrix (VR or AR are both possible!) and control your Vehicle or Drone using a Commlink or an RCC. As noted in other posts, you primarily use mental attributes during remote operation for stuff like Gunnery. It also sets your [Data Processing] stat as one of your potential limits for operations.
1) Rigging. This is also referred to as "Jumping In" it causes your consciousness to become one with the machine. This requires a Control Rig implant as well as going into VR (Hot or Cold.) It also requires your vehicle/drone to have a rigger interface (standard in drones, must be bought in vehicles.) The upside is you get a bonus to dice pools due to rigging (+2 base, +X for control Rig rating and possibly +2 for hot sim!) The downside is when your vehicle takes damage, you get 1/2 of the damage as biofeedback just like you were hit too.
Last note is that the lower the number that I put next to the method, the higher the priority in resolution. So unless you cut out the vehicle's recieving circuits, both Remote Control and Rigging override Manual Control. All methods override Autopilot.