A Farad is the unit of capacitance that will store 1 coulomb of charge when it has a potential of 1V across it. Alternatively, if current is flowing into it at 1A, the voltage rises by 1V per second.
1 Farad is ENORMOUS. Large capacitors are measured in thousands of microfarads, small ones in fractions of a billionth of a Farad.
A watt is a measure of the rate at which you are expending energy. 1 Watt is 1 joule per second. If a resistor has 1A flowing through it, and 1V across it (which implies it is a 1 Ohm resistor) then 1 joule of energy is being expended each second. Thus, it is expending energy at a rate of 1 Watt.
This rate is called power (more power means more energy per unit time), and is often designated P.
Similarly, I is current (in amps); V is voltage (in Volts); and R is resistance (in Ohms).
There are a number of equations that relate them to each other.
V = I * R
P = V * I
From these, you can rearrange and substitute to find any of these in terms of any other two.
Look at Ohms Law on wikipedia for more information.
Note that the definition of the capacitor has a 1 F capacitor charging at 1A for 1 second and having 1V across it. This DOES NOT mean it is dissipating 1W because a capacitor stores energy, it doesn't waste it like a resistor. (in practice it wastes a little).
To properly understand capacitors you need to understand calculus (an possibly differential equations).
as an example, the relationship between capacitance, voltage, and current is given by this: i = C * dv/dt Note that time is involved!