Storage controller, storage system and method of operating the same

A storage controller includes parallel input channels configured for simultaneously receiving data from substantially redundant memories, an error estimation unit, a decision unit, an error correction unit and a selection unit. The error estimation unit generates error information by estimating an error level of the plurality of data. The decision unit performs a logical operation on the plurality of data to generate operation data. The error correction unit generates error correction data by correcting an error of the operation data. The selection unit selects one of the operation data or the error correction data based on the error information.