Coffins and caskets are both used for burials in Australia. The main difference between the two is the shape, and the opening mechanism. When you think about burial you typically picture a coffin - which is a six-sided container that is wider up the top around someone’s shoulders and tapers in at the bottom. Coffins have a hinge along the side which allows you to flip open the whole lid, and it has handles on either side to carry it.
A casket on the other hand, is typically a rectangular shape with no variation in width. They usually have a lid that is split down the centre, so the lid can be opened to expose the top half of the body during open-casket viewings. Since they tend to be on display during funeral services caskets are usually constructed with extra features like cushions and interior linings which can make them more expensive than traditional coffins.