Pointer vs Array in C

Most of the time, pointer and array accesses can be treated as acting the same, the major exceptions being: 
 

1. the sizeof operator

• sizeof(array) returns the amount of memory used by all elements in the array 
• sizeof(pointer) only returns the amount of memory used by the pointer variable itself 

2. the & operator 

• array is an alias for &array[0] and returns the address of the first element in the array 
• &pointer returns the address of the pointer 

3. a string literal initialization of a character array 

• char array[] = “abc” sets the first four elements in array to ‘a’, ‘b’, ‘c’, and ‘\0’ 
• char *pointer = “abc” sets the pointer to the address of the “abc” string (which may be stored in read-only memory and thus unchangeable) 

4. Pointer variable can be assigned a value whereas an array variable cannot be.

int a[10];
int *p; 
p=a; /*legal*/
a=p; /*illegal*/ 

5. Arithmetic on pointer variable is allowed. 

p++; /*Legal*/
a++; /*illegal*/ 

6. Array is a collection of similar data types while the pointer variable stores the address of another variable.

Please refer Difference between pointer and array for more details.