Methods of programming multi-level cell nonvolatile memory devices and devices so operating

A method of programming in a nonvolatile memory device, the nonvolatile memory device including a plurality of memory cells that are programmed into multiple states through at least two program steps, the method comprising:

• performing a primary program from an erase level to a first target level with respect to the memory cells coupled to a first word line;
• performing a preprogram from the erase level to a preprogram level in association with the primary program with respect to the memory cells coupled to the first word line, the preprogram level being larger than the erase level and smaller than the first target level;
• and
• performing the primary program with respect to the memory cells coupled to a second word line adjacent to the first word line;
• and
• performing the preprogram with respect to the memory cells coupled to the second word line.