Final answer:
Special instructions for immediates are used in assembly language to include values directly in the instruction, leading to faster execution by reducing memory accesses. They are efficient for small values but limited by the size that can fit within an instruction.
Step-by-step explanation:
Special instructions for immediates refer to a type of instruction in assembly language or machine code programming where the instruction itself contains the value (or immediate) to be operated upon, rather than an address pointing to the value. This implies that there is no need for additional memory accesses to fetch the actual value, leading to faster execution times for these instructions.
One characteristic of immediate instructions is that they can make the code more efficient by reducing the number of memory accesses required. Another characteristic is that they are typically used for small constant values because there is a size limit to how large an immediate value can be; it must fit within the instruction itself.
For example, an add operation that adds a small constant to a register would use an immediate instruction. However, they are not suitable for operations requiring large constants or variables, as these would not fit into the instruction and would therefore require memory access.