what is a blockchain in easy terms 
imagine you typed some information into a document on your computer and sent it through a program that gave you a string of numbers and letters called hashing with the string called a hash you add this hash to the beginning of another document and type information into it again you use the program to create a hash which you add to the following document each hash is a representation of the previous document which creates a chain of encoded documents that cannot be altered without changing the hash each document is stored on computers in a network this network of programs compares each document with the ones they have stored and accepts them as valid based on the hashes they generate if a document doesn t generate a hash that is a match that document is rejected by the network 