Bitcoin Forum

Which one is better? for a store a data that will determine the supply chain of say medicine.

What information you really want to get? I would personally go to Private Blockchain especially when it comes to data

Well, that depends on the reputation of the blockchain owners. Public blockchain are decentralized and less secure and private blockchain are more secure but they are centralized and ruled by a corporation.

It depends on the data you want to store in the blockchain. Is it sensitive then private blockchains are your way to go, if not, you may consider public chains, too. There really is no "which one is better".

As mentioned above it depends on the amount of access you can allow. Private blockchains has all the qualities of the blockchain technology and anyone who is granted access to the data stored can view it, but it is still immutable.

Public blockchains are more suitable for public enterprises, with open shares to the public.

If it's for private use then it's better for it to be private, as transparency isn't necessary. Heck, a good old database may even be better than any blockchain in the case you're describing.

If it's for a partnership of several stores to track inventory, etc., a public blockchain may work.

Public Blockchain : If you want provide details in public we can make public blockchain .Bitcoin is good example for public blockchain .

Private Blockchain : Only few people will involved in this kind of private blockchain .Government process and voting system will make private blockchain .

It's down to your choosing really as the both of them are really OK and convenient to use.
Another determining factor would be the content of the data, considering public blockchains,information is privy to all, if it's a sensitive content then the private blockchain would do just fine.
But in them both your files are safe, as the documents cannot be altered

You can make a public blockchain. Decentralized governance and DAO (Decentralized Autonomous Organization) do exist. And there are few projects with it. Sure don't hope to see such system by a government, but a governance is really possible. This is what Horizen is working on with the founder of IOHK (also the founder of Cardano, don't ask me his name)

It depends on what the project end goals are and what your looking to achieve. The examples that others have given should be enough to get you going.

There is no better or worse when it come to the level of accessibility allowed on the chain, just choose whichever suits your desires.
I'm more interested in what algortithm is used to run the blockchain and how it is designed to meet it's requirements

if you dont your data to been seen by public you must go with private blockchain and if its ok that your data is accessible by public then go with public blockchain

but your question description is only incomplete 

- If it is for a single entity/company, then a common SQL database would be the better solution.
- If it is for multiple different entities/companies, in theory, you could use a private blockchain.

I don't see a public blockchain is useful for supply chain data.