We have seen that number of instructions that can be provided in a computer depends on the signal lines that are used to provide the instruction, which is basically the size of the storage devices of the computer.
For uniformity, we use same size for all storage space, which are known as register. If we work with a 16-bit machine, total instructions that can be implemented is 216.
The model that we have described here is known as Von Neumann Stored Program Concept. First we have to store all the instruction of a program in main memory, and CPU can work with the contents that are stored in main memory. Instructions are executed one after another.
We have explained the concept of computer in very high level abstraction by omitting most of the details.
As the course progresses we will explain the exact working principle of computer in more details.