it is not different it is both the same but some have 4 sides and some have 6 sides.
Correction:
The above answer relates to the difference between coffin and casket.
A sarcophagus was originally (in ancient times) a burial receptacle made of stone.
In modern parlance, it is a highly luxurious coffin or casket (often made from cast bronze).
A sarcophagus!!!! The stone coffin in which a wood coffin was placed is a sarcophagus!!!!!!!!!!!!!!!!!!!!!!!!!
A synonym for the word "sarcophagus" is "coffin."
A Sarcophagus
Thet are called sarcophagi.
Sarcophagus looks like a coffin, but sarcophagus have faces and are painted with bright beautiful colors. Some of them are covered in gold if they were kings.
The Egyptians sarcophagus often contained a coffin and an inner coffin known as a mummy board. Both the sarcophagus and the coffin could be very plain or extremely ornate.
sarcophagus
It is a sarcophagus.
A sarcophagus is a stone coffin. A coffin is a box like item where dead people are placed for burial.
The stone container of a wooden coffin was called a sarcophagus.
Sarcophagus
Sarcophagus