For memory based stuff, at least as far as cheats were concerned, they were rare and everything would be in the same place boot after boot after boot with no scope for any change. In newer code/languages you have the option to run all sorts of bits of code in different orders, and have the code handle noting where things are in memory rather than typically having them baked into the code. You also have the option to have tables increase infinitely (or until you run out of memory) which also necessitates pointers. Or if you prefer a game might have said you only have 50 inventory slots because it had assigned only the space necessary for it, today a game can save effectively infinite slots by just adding more on to the end. If there is more on the end then if the next bit of code is directed to be stored after it then having addition items means it might be shuffled forward between boots or that part of the game being loaded. Likewise if a piece of code fails to release memory after it is done, or continues to add and add and add to the memory it sections off you get a memory leak but that is not really necessary to contemplate too much right now other than to say a game might release code from memory it is not using at that point in time and thus mean your cheat does nothing as it is literally not there in memory to do anything with (you get a minor variation with older consoles as well where a cheat might work in game but crash when it is booting up because the cheat engine does not care but the game does). There is also something called ASLR, address space layout randomisation. It is a fairly weak security feature but is a thing to tackle. Here it was noted that a lot of exploits (and cheats but nobody really cares about that) relied upon having things land in predictable locations in memory.

If you jumble this up (easy enough to do if you build your program with it in mind) randomly then the exploits work less of the time if they can't rely on something being somewhere in memory. It can also mean your data you wish to cheat with is not in the same place, that your injected code might not be in the same place and more besides.

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