What is near far and huge pointers How many bytes are occupied by them?

Answer 1

Near, far, and huge pointers are different types of pointers used to reconcile the different addressing models of the Intel 8086/8088 class processors, running in a 16-bit operating system such as Windows 3.x, as well as any of the newer incarnations running in real mode or virtual 8086 mode.

A near pointer can address something within one 64Kb memory segment, containing only an offset, and it takes two bytes. The segment is implied by context, and is usually the data segment, selected for the addressing model.

A far pointer can address anything in the 1Mb memory1, containing both a segment and an offset, and it takes four bytes.

A huge pointer is a normalised far pointer, which means its offset part is always between 00H and 0FH.

In 32-bit mode a pointer can address anything in 4Gb memory, containing a flat 32-bit offset, and it takes four bytes. (In this mode segments have no significance.) It only works, however, when there is support for it, such as the WIN32 extension of Windows 3.x.

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1In the 80286 or higher, running in protected mode, in OS/2, the segment portion of the pointer is actually a descriptor selector, so 1Mb addressibility depends on the operating system environment.
far huge near pointer is an oxymoron. far points to memory outside of the normal address space. near points to memory within the normal address space, is the default, and usually is not needed. I've never seen huge before. What is the target architecture?
Near, far, and huge pointers are a construct (usually) in the Win16 environment running on an 8086/8088 or later in real mode, such as Visual C/C++ 1.52. In this environment, near pointers are 16 bits, and far and huge pointers are 32 bits.