Figuring out how to use a DC motor to rotate a solar cell towards the sun

As described in the subject, I am building a mechanism that will rotate a solar cell to the face of the sun (Very crucial to project, electricity generated will be used to recharge used batteries). I propose putting at least 4 photodiodes on each corner of the solar cell to see the area where the solar cell would receive the most sunlight and using a DC, stepper, or another type of motor to rotate the solar cell accordingly. I am facing an issue with deciding the best type of motor that will go with my project and its needs. Please explain how each motor is different and what be the best approach for rotating the solar cell in my project.
I am powering the Arduino board itself with a wall adapter and I am going to use arduino board UNO, unless a different approach is suggested for the type of arduino board i should use as well.

Please just google this, its been done loads of time before.

E.g
Use the key words

Arduino solar tracker

Also there's no need to have the cells in each corner, you can put them together with an X-shaped vane between them. That has been done a 1000, the above-mentioned Google search should find examples.


Rob

Light Dependent Resistors (LDRs) may be easier to use. Just put a shield between (for example) the left/right pair so they can only both get full sunshine when the panel points directly at the sun. Use your Arduino to move the panel towards the brightest LDR in small steps. Use a DC motor with a worm drive so it won't move when the power is off. Don't use a stepper motor - they use more electricity than the solar panel produces.

...R