If in a computer ; 16 bits are used to specify address in a RAM, the number of addresses will be
If in a computer ; 16 bits are used to specify address in a RAM, the number of addresses will be 65,536.
A 16-bit integer can store 216 (or 65,536) distinct values. In an unsigned representation, these values are the integers between 0 and 65,535; using two's complement, possible values range from −32,768 to 32,767. Hence, a processor with 16-bit memory addresses can directly access 64 KB of byte-addressable memory.
Yes, on a 32bit machine the maximum amount of memory usable is around 4GB. Actually, depending on the OS it might be less due to parts of the address space being reserved: On Windows you can only use 3.5GB for example. On 64bit you can indeed address 2^64 bytes of memory.