Bitcoin, being a blockchain-based cryptocurrency, consists of transactions that takes place within a network that is recorded on a blockchain. A blockchain is a public ledger that can be seen by anyone, but cannot be changed by anyone. This ledger is made up of blocks that fit together cryptographically.
When a user makes a transaction, the transaction is included in the block that is being mined at the time and is then confirmed by the blocks that follow. The more blocks placed upon after your transaction, the safer your transaction will be.
Transactions are made up of data that is composed of the information regarding the transaction itself. This data, like any other, takes up space on the block it belongs to.
Currently, each block on the Bitcoin blockchain has the ability to hold 1MB of data, which means that the block size of bitcoin is 1 megabyte. In other words, there is a limit to the amount of transactions that can fit in Bitcoin's blocks, but it wasn't always like this.
While many claim that a block size increase would put too much "weight" upon nodes and miners, but given the increase in storage requirements, the blockchain size would not just suddenly increase overnight, rather, it would simply allow the network to grow as the demand grows.
Interested to buy Bitcoin? Check the Market Now https://www.bitkub.com/market/BTC