Whether a given electrode acts as anode or cathode depends upon the other electrode with which it is coupled within an electrochemical cell.
In electrochemical series, different half cells have been arranged in the order of increasing standard reduction potential with respect to standard hydrogen electrode.
The measure of ability of an electrode to undergo oxidation is referred to as it oxidation potential.
The measure of ability of an electrode to undergo reduction is referred to as its reduction potential. A cell can be constructed by coupling two electrodes.