As we already know, on January 3, 2009, a genesis block was created in the bitcoin network, thank you, Satoshi. Since Bitcoin was literally worthless at the time, only a few Bitcoin was mined. So the mining was available even from your laptop. All calculations were done by the processor and the approximate mining complexity of the unit was 4Gh/s. Mining performance is measured in hashes per second - h/s. The hashrate of the device is determined by its performance and computing power, the hashrate of the network depends on the number of miners and equals the total power of active devices in the network. The complexity of the network is regulated by the difficulty of the problem solved to obtain the block: to find the required hash. The difficulty of the task depends directly on the hashrate and changes automatically. The more miners connect to the network, the higher the performance and complexity, and the more difficult it will be to extract cryptocurrency. The network complexity divided by the hashrate value equals the block time. This time the network maintains constant. At the time, the Intel Pentium 4 processor was producing 1.29 Mh/s. This meant that with one processor, it took about 50 minutes to extract the unit. And the miner received not 6.25 BTC per block (as now), but as many as 50 BTC! In order not to be eaten by FOMO and the thought of "if I started mining in 2009..." it is worth recalling that then Bitcoin was not worth anything. And I don’t think any of the miners of that time would think that any digital coin they’re getting in 13 years could be worth up to $67,000.