What is the maximum number of unique addresses memory can have based on the processor's bitness?

The maximum number of unique memory addresses is determined by the processor's bit width and is equal to 2 raised to the power of the number of address bits.

For example:

• A 32-bit processor can address 2^32 = 4,294,967,296 unique addresses (usually bytes), which is 4 GB of memory.
• A 64-bit processor can address 2^64 unique addresses, which is theoretically very large (about 18 quintillion bytes), but in practice, it is limited by architecture and operating system.

Thus, the formula is:

Maximum number of addresses = 2^(processor bit width)