Now a days there are so many coins available in the market some of them are based on bitcoin technology and some of them are based on ethereum, if I am developing a website which is dealing with both of them how would I determine which coin is based on which technology because both the technologies have different daemon commands and different jsonRPC
Just go to the github project and try to find out if it's a fork of Bitcoin or if it's a fork of Ethereum, it should be easy to see by looking at the branches and where the project comes from, also usually the ANN thread here in Bitcointalk (every alt has an ANN thread) should contain this information and if not you can ask directly to the developers.
