What is Double-Spending?

• One of the main reasons for the failure of digital currency creation attempts before bitcoin is double spend problem. Although many attempts have been made to create a "universal digital currency" within the time frame prior to the creation of Bitcoin and its universal character, these attempts have been unsuccessful due to the "double-spending problem" and have failed to achieve its purpose.

• Bitcoin has been successful and has the opportunity to become a universal digital money because it has removed the problem of Double Spending.

Double Spending

• The double-spending problem means that 'the same digital currency' is used by owner for multiple purchases , which means that one of the sellers can not be paid. The malicious users on the system cause one of the sellers to be cheated by using multiple purchases of the same currency, sabotaging the operation of the system by reducing the reliability of the digital money mechanism.

As a solution to the double spending problem: Blockchain and Bitcoin

• Bitcoin theoretically carries the risk of copying and re-transferring, that is, doubl spent, just like the previous digital money itself. But bitcoin makes this possibility theoretically, but it makes it almost impossible to reduce the risk of being spent twice in a practical context. In this way Bitcoin solves the problem of "double spending" and does not carry the risks posed by its previous digital money. One of the main reasons for the universal prevalence of bitcoin is that it has practically solved the problem of "double spending".

• Bitcoin manages the double spending by implementing a confirmation and consensus mechanism and maintaining a blockchain, distributed ledger technology.

• Bitcoin’s blockchain maintains a chronologically ordered, time-stamped transaction ledger from the very start of its operation in 2009.

• Every 10 mins, a block (i.e. a group of transactions) is added to this ledger accordingly. Then all the nodes on the Bitcoin network keep a copy of this global ledger.