-I don't understand. Wikipedia was no help and it seems like if you care about it, you already know the answer. So if someone could put it into laymans terms that would be awesome :)
(secondary question) the difference between 32 and 64 bit applications is that 64 apps can take advantage of the processor while 32 are stuck where they are at?The difference is in how much information can be transferred through your computer in each cycle of the cpu. It's easier to talk about smaller numbers of bits, but the application is the same, just on a bigger scale. So, here we go...
Start with one bit. One bit is the smallest amount of information you can pass. It is the building block of computers. It is like a light switch. It can be in one of two modes - off or on. In computer terms, thats called a Zero or One.
Two bits give you more choices, because one could be on while the other is off. But the outcome is multiple, or actually exponential. The options include:
Off - Off
Off - On
On - Off
On - On
The next bit (three bits) would give you any combination of three off/on switches. So, the more bits you have, the more choices you have, thusly, the more information you could pass in a single cycle. To get an idea of how quickly it rises, your monitor can show colors in 8 bits per color channel, red, blue, green. This gives you 256 levels for each channel, but furthermore, it gives you a total of over 16 million colors in 24 bits (8 x 8 x 8). If you added just a few more bits per channel, you could get into hundreds of millions of colors.
What does this have to do with 64 bit versus 32 bit? Well, one real life example is with RAM. A 32-bit system can only use a maximum of 4 GB of RAM. A 64-bit system could us a lot more than that. Also, look at video game systems. The old 8-bit Nintendos were superceded by 16-bit Sega, and we continued moving up to 32 bit, 64 bit, and now 128 bit gaming systems. The complexity of the games, not to mention the awesomeness of the graphics, goes up exponentially.
For a 64-bit system to work as effectively as possible, you need to have 64-bit hardware, Operating System, and Applications. We are just beginning to see true 64-bit applications come along. In a lot of cases, 32-bit is still good enough, so the move is slow. Probably, the only reason the world ever did move to 64-bit computers, is the RAM issue mentioned above. Windows and some applications were getting to greedy with RAM, so 4 GB became not-enough in some cases.
The width of the data bus inside the computer is different. A 64-bit CPU can add two 64-bit numbers in one go while it takes a 32-bit one two goes. In software, that may affect the definition of an integer - whether it's a 32-bit or 64-bit quantity.
All the Intel family are backwards compatible, so that programs that run on older CPUs will still run on newer ones, and all the old 32-bit instructions are still available. So the old programs run fine. On Linux, 32-bit programs need 32-bit libraries installed, so that you may find systems where the admin has not loaded them to save space, or to discourage legacy software, and the 32 bit versions will not run. That may eventually happen on Windows too.
From the perspective of the average computer user, the most significant thing is that a 32 bit system can't have more than 4GB of memory space. This has to include the memory spaces of your graphics card and other hardware, once those are subtracted from the 4GB then what's left can be used for RAM. A 64 bit system can access more memory than you can get in any home computer today.
So with a 32 bit system if you have 4GB of memory and a 1GB memory card then you'll only be able to use less than 3GB of your memory, and adding more memory won't change this.
64-bit Windows 7 has hardware backed DEP while 32-bit Windows 7 is software based.
The bytes compression on the clusters.
32 can run 64, but 64 can not run in 32.
Almost ALL newer processors are 64 capable.
Soon it won't matter about this little known technology of 32 bit.
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