1. A nonvolatile memory device comprising: a memory cell array including a plurality of multi-level cells; and a control unit configured to determine a characteristic of data to be stored in the memory cell array, wherein the control unit is configured to select one of plural multi-bit programming methods with based on the determination, wherein data is stored in the memory cell array according to the selected multi-bit programming method, and at least one of the plural multi-bit programming methods maintains least significant bit (LSB) data when there is a program fail of most significant bit (MSB) data.