Array, Structure, Union, Function in differences in data structure

1.       Difference Between Call by value and Call by reference

2.       Difference Between Array and Structure

3.       Difference Between Library Function and User Define Function

4.       Difference Between Macro and Function

5.       Difference Between Structure and Union

6.       Difference Between ASCII File and Binary File

1.     Difference Between Call by value and Call by reference

Call by value	Call by reference
In call by value, a replica of actual arguments is passed to formal arguments of the called function.	In call by reference, the address of actual arguments is passed to formal arguments of the called function.
In call by value method the called function works with dummy arguments.	In call by reference method the called function works with actual arguments.
In call by value, actual arguments will remain because it is, they can't be modified inside function.	In call by reference, actual arguments can be modified inside function.

2.    Difference Between Array and Structure

Array	Structure
Array is a collection of variable of same data type that share common name.	Structure is a collection of variables of different type that share common name.
Array is also called derived data type because it is derived from primary data types.	Structure is called user define data type because it is defined  by user as per his requirements.
Array elements are often accessed by specifying index as a subscript along side array name.	Structure members are often accessed using dot operator  along side structure variable and member name.
Accessing array elements take less time as compared to structure.	Accessing structure elements take more time as compared to Array.

3.    Difference Between Library Function and User Defined Function

Library Function	User Define Function
There is no need to declare and define library function.	Programmer must have to declare and define user define functions.
In order to use library function programmer have to include header file.	In order to use user define functions programmer does not  have to include header files.
They are predefined in header files.	They are defined by users as per their requirements.

4.    Difference Between Macro and Function

Macro	Function
Macro is Preprocessed. There is no need to compile it.	Function need to be compiled.
Execution of function is slower.	Execution of macro is faster.
Consumes less memory.	Consumes more memory.
Macro cannot be extends beyond one line.	Function can extend up to any number of line.

5.    Difference Between Structure and Union

Structure	Union
Compiler allocates separate memory for every member of the structure.	Compiler allocates common memory space for all members of union such it can accommodate largest member of the union.
Hence all the member having separate memory allocation we will use all the structure members at same time.	Hence all the members having common memory allocation we will use just one member of union at same time.

6.    Difference Between ASCII and Binary File

ASCII File	Binary File
It occupies more memory space as compared to computer file .	It occupies less memory space as compared to ASCII file.
It is less efficient.	It is more efficient.
Some characters may be “hidden” from file even if the characters are still in the file.	You can access every byte in the file.