What is the difference between occurs 0 and occurs 1?

occurs 0 is key a word in abap used to create memory in body area , when ever we declare occurs 0 the system will allocates 8bytes of memory and it keep incrementing the memory to 8bytes every time.

occucs 1 is a key word in abap used to create memory in body area of an internal table. it allocates memory for one records only, and keep incrementing every time by one record memory.

Mostely prefered one is occurs 1 , in order to reduce the wastage of memory.