cs segment register points to the code segment.Note: although the exigencies of limited resources and/or basic machismo have in the past caused people to write programs which modify their own code, this is generally considered today as a bad practice, as (a) such programs are non-reentrant so that recursion becomes a problem and multiple instances of the program cannot be run from the same memory image and (b) many modern computer architectures with Harvard-style caches (separate caches for code and for data) require the entire cache to be flushed if the code is modified, therefore degrading performance. Don't do it.