Price is one of the main factors discussed when talking about Bitcoin. Its dynamics are closely watched by all involved. However, the price is not what allows the system to work. Rather, it is consensus rules implemented in the network that are more essential.

There is a consensus rule in Bitcoin that defines what will be considered legitimate on the network. This includes whether a transaction adheres to the protocol and whether the blocks created by a miner are valid according to the protocol or not. Also, the consensus rules in the network define the supply of Bitcoin and how it should be gradually decreased till the moment it reaches the 21 million limit. This happens due to the block reward that halves in roughly four years.

Consensus rules are necessary because unlike in the company where everything is decided by the central authority, transactions in Bitcoin are validated by different participants using software that validates the blockchain according to certain rules.

But this is where things get much more exciting in regards to Bitcoin because the set of rules defines the environment that enables thousands of independent computers to come to an agreement on their shared history.

The Proof of Work is an example of the aforementioned rules that enable mining and validation of new blocks by miners and nodes respectively.

What is important is that each block in Bitcoin's blockchain is connected to its predecessor, thus making it increasingly harder to rewrite the previous history as the number of blocks increases.

Bitcoin's set of rules is also changeable as any update requires updating the software of the network. Over time, Bitcoin has had both soft forks and other types of protocol updates.

So the price tells us what the market currently thinks about the price of bitcoin. And the rules tell us what Bitcoin really is. Without them the price would simply be a number without any underlying substance.