Integer members can be stored in memory areas smaller than the compiler would normally allow in C and C++. Bit fields are these space-saving structural elements, and their breadth in bits can be explicitly stated.
The size (in bits) of structure and union members can be specified in C. When we know that the value of a field or group of fields will never exceed a limit or will be within a restricted range, the aim is to use memory efficiently.
The bit field is a highly significant component in the C language, and it is supported by structure and union. The bit field allows data to be packed into a structure or union without wasting memory.
Some bit field members are stored in memory from left to right, whereas others are stored from right to left. If bit fields are excessively large, the next bit field may be placed in memory sequentially (overlapping the memory boundary) or in the next word of memory.
A bit field is a data structure made up of one or more adjacent bits that have been assigned to specific functions, allowing any single bit or group of bits to be set or inspected.