Hash Funcation in Blockchain

Almost everyone has heard about blockchain. But not every one understands how it works. This blog shows that understanding blockchain is a five finger exercise .

Let's Imagine there are ten friends(ram, shyam, ben, clarks, Roni, Johnny, Golu, Tony, Gatsby & Ann) who have came into an agreement that whatever monetary transaction they are doing shall be recorded by Ram

Ram recorded following transactions:-

1. Ben gave $200 to Roni
2. Roni gave $50 to Gatsby
3. Johnny gave $150 to Ann
4. .........

Now lets suppose Gatsby decided to change the entries

1. Ben gave $200 to Roni
2. Roni gave $50 $60 to Gatsby
3. Johnny gave $150 to Ann
4. .........

Ram Noticed that someone has changed the entries. So he decided to come up with a way such that he converted every statement into a code. Each new statement is converted into a code in such a that it made from code of previous code and code of new statement.

1. Ben gave $200 to Roni  - 059fa39a6995d4b9be5831efeecac273

2. Roni gave $50 $60 to Gatsby - 3579c246cad30148864861e29428b701

For generating final code for 2nd statement ram inserted code generated by previous statement code+ current statement code

   8a198a43b29739922a3c3d102e4c23d5

And so on .........

This code is called as hash. So if now Gatsby tries to change hash so he has to change all the hashes. When there are multiple transaction this becomes very difficult as to crack very last hash person hash to crack all the hashes.