Bitcoin is a decentralized cryptocurrency. The transactions are peer-to-peer and recorded in the blockchain. The interesting thing is you can mine bitcoins, but it is very resource intensive. I first started bitcoin mining in the mid of 2014 using my laptop. I used GUIMiner and CPUMiner together, but it gave me a combined hash rate in the ranges of MH/s with a dual graphics card (ATI) and a quad-core CPU (AMD). I used pool mining connecting to slush pool. But GPU mining is not good as it can damage the card and also the output is very negligible. So I bought a Bitfury Twin Chip USB ASIC bitcoin miner which gives a hash rate of 5 GH/s.

I also purchased 10 GH/s cloud hashing power for CEX.io from ebay which actually was sold for a higher price than its actual value. At that time the only way to buy the hashing power was from the users selling it at ebay as CEX.io does not have credit card facility (but now they have added). Or you can convert bitcoins for hashing power. For that you must first have bitcoins, which you can buy from other bitcoin exchanges that accepts credit cards and then transfer it to CEX.io and trade it for their hashing power.

I also purchased Technobit Hex16B miner which contains bitfury ASIC chips with a total hash rate of 20 GH/s. I pointed the mining rigs to the local stratum proxy which then connects to ghash.io, which is where the CEX.io also does pool mining. Any one can connect to ghash.io and do pool mining.

To my dismay, the Technobit ASIC miner did not work. Neither I nor the person from Technobit got this to work with my system. I connected the miner to a PSU, and my system to the miner using HEX Miner under Windows. But it still gave proxy auth error.

So I compiled CGMiner with bitfury and other flags enabled under Ubuntu, but no success. It detects and mines from the USB miner but not the HEX16B. So I bought a TP-Link TL-MR3020 with the assumption that it might be my laptop (Windows 8, XP), drivers or something causing the HEXMiner software to not work with Hex16B. You need to update the TP-Link Wi-Fi router firmware from the one provided by Technobit. But in the process I think I bricked the device. I doubt that the miner was faulty to begin with and finally it was lost into oblivion.

The thing about bitcoin is that as more people starts mining, the difficulty increases and the hash power which mined 1 BTC previously will start giving lesser BTCs. So to keep up, you need to add more miners, which in-turn increases the power consumption, heat generation, noise, space consumption etc. Also consider the shipping cost of these miners. So I finally decided to stick with cloud mining. You only have to pay the maintenance fee deducted in BTC from the rewards. And the best and reliable service was provided by CEX.io which started in 2013. Now they stopped providing mining service altogether. One advantage with CEX.io was that when it mines Bitcoin, it will also mine altcoins like Namecoin, Litecoin etc. They also provide provision for trading coins, so these altcoins can be exchanged for mining power or bitcoin or vice versa.

I mined, traded for a year and then stopped as I don't see much returns and had to spend a lot of time keeping track of the price, hashrate variations etc. I traded all compute power to BTC and some to NMC and transferred to my wallets.

Namecoin is an interesting idea that you can have decentralized, censorship resistant DNS based on Bitcoin technology. The DNS address can be registered which will give you a .bit address and you own it. But the address needs to be renewed after some time by paying NMC. The expiry was around 6 months at that time. Registered a couple of them, but stopped renewing as I don't mine anymore.