NX bit

The nx bit (also known as the No-Execute bit) is a special feature in computer systems that helps to keep them safe from bad software or computer viruses. Imagine you have a box of cookies, and there are some cookies that are yummy and some that are yucky. If you eat a yucky cookie, you might get a tummy ache. Now, what if you could know which cookies are yucky and keep them from being eaten? That's sort of what the nx bit does, but with computer programs instead of cookies.

When your computer runs a program, it gives it permission to access certain parts of the computer's memory (kind of like how you have permission to eat certain cookies in the box). This memory contains important information that the program needs to run properly. However, sometimes a bad program might try to access parts of the memory that it's not allowed to, and this can cause all sorts of problems for your computer (like a tummy ache from a yucky cookie).

So, the nx bit helps to keep bad programs from accessing certain parts of the computer's memory. It does this by marking some parts of the memory as "non-executable," which means that no program can run code from that part of the memory. This way, even if a bad program tries to access that memory, it won't be able to execute any malicious code and cause harm to your computer.

In summary, the nx bit is like a filter that helps to keep bad programs from taking over your computer. It marks certain parts of the computer's memory as off-limits to programs, so even if a program tries to access those areas, it won't be able to execute any harmful code.