And when we do what happens next?
You can choose but you need to make it clear and since the will is not normally read until after the "funeral" best to set up your preferred arrangements at the same time as you write your will.
Personally I am donating my body to science. This means I must contact a teaching university and they will provide the necessary forms which need to be completed, signed and witnessed.
I have, of course, consulted my nearest and dearest on the matter and none have any objections.
The medical school will take the body, use it for teaching purposes for up to three years and then arrange disposal according to my wishes ie cremation or burial with whatever religious or humanitarian ceremony I desire. They will also arrange a memorial service, again of whatever type I prefer, for those who wish to attend such. The medical school will cover all costs involved thus relieving my family of any financial burden whilst providing those that feel the need the opportunity to say "Goodbye".
Frankly my reasons are mainly that I have so many things wrong with me it may be of use to future patients if the doctors get the chance to look and see before they start on live patients. Also I don't want any arguments along the lines of "He would have wanted etc......" My way takes care of all that nonsense.