Answer:
Current (symbol: I) is a drift of electrical charges through a conducting material, expressed in amperes.
Voltage (symbol: E, U, or V) is another word for potential difference which, in layman's terms, provides the 'driving force' for current, and is expressed in volts.
Resistance (symbol: R) is the opposition to current, and depends on the length, cross-sectional area, and resistivity of the conducting material, and is expressed in ohms.
Resistance is the ratio of voltage to current, in other words: R = U/I