In the previous sections, we said that all nodes store identical copies of the blockchain database, didn't we?
And that's an issue that undoubtedly results in a lot of data storage and redundancy. However, it is the price we have to pay in order to obtain a truly decentralized peer-to-peer system without any middlemen.
Moreover, datasets can be different in size, some blocks may have 200 transactions, other blocks may have 500 transactions, and others may have 1,000 transactions. All these transactions also typically vary in the size of the information they contain in terms of kilobytes. The only capacity limit in the Bitcoin blockchain protocol is on the size of each block, which has been 1 megabyte since 2010. It was recently amended to effectively 1.4 MB with the latest upgrade of the Bitcoin software. But again, block sizes can vary up to that limit...