Corrosion of metals and alloys in an aqueous environment is generally an electrochemical process that requires four essential components: an aqueous electrolyte, an anode, a cathode, and a current carrying pathway (i.e. circuit). In electrochemical corrosion, the anodic oxidation reaction should be compensated by the reduction reaction at cathode. The basis for the types of corrosion is their appearance and propagation mode. The eight well-known forms of corrosion are uniform or general corrosion, galvanic corrosion, pitting corrosion, crevice corrosion, intergranular corrosion, dealloying or selective leaching, erosion corrosion, and environmentally assisted cracking. Apart from these eight forms, the microbiologically influenced corrosion is also considered as one of the important corrosion forms. Nondestructive technique plays a vital role for damage assessment and life extension of the component as it is suitable in detection of the early stages of corrosion so that corrective measures can be taken before damage becomes severe.