sizeof Operator in C/C++: Determining Data Size

'sizeof' is an operator in the C and C++ programming languages that returns the number of bytes occupied by a datatype or variable in memory. It is used to determine the size of an object or data type, which is important for allocating memory and performing operations on the object. The syntax for 'sizeof' is:

sizeof(datatype or variable)

For example, 'sizeof(int)' would return the size of an integer in bytes, while 'sizeof(char*)' would return the size of a pointer to a character in bytes.