"Can you explain "mining" ? I could not make head nor tail of the wiki explanation."
Basically it's maths. Cryptography. There are millions of computers around the world working on arbitrary maths problems. Every 10 minutes they (all the computers working on this) are awarded some bitcoins (this is not awarded by some central authority, but by consensus - you get confirmations from other computers on the network, and given sufficient confirmations then you can assume that it's valid (because one computer could be running a hacked version of the code, but if you demand multiple confirmations that wouldn't work)).
Each bitcoin is currently worth something around £10k but even this figure is uncertain even at a given point in time, because matching a holder of bitcoins (arbitrary numbers on a computer) with holders of cash wanting to exchange cash for bitcoins is not as easy as most other assets.
For example, you can sell your pounds to Transferwise and have a foreign currency in less than 24 hours in a foreign bank account at a cost of under 1%, even in relatively shitty unstable foreign currencies.
But there are zero reputable places to sell bitcoins, and the 'price' quoted varies sometimes by 10% or more between different venues, and there are often limits on selling and buying.
And selling is not as easy as, say, selling a car. If I sell you my Ferrari for £1 million, then you give me the Ferrari and I transfer the cash to your acount, and there's a good chance we can trace both cash and Ferrari if things go wrong.
But if someone knows your Bitcoin details, they can steal them and that's totally unreversible.
In comparison:
Bitcoin vs shares:
- Shares generate an income and this will tend to increase over time, whereas bitcoin generates no income
- Shares an easily be sold at relatively low cost (around £10/deal), Bitcoin cannot easily be sold and the cost to sell may be high
- Popular shares are highly liquid and relatively stable, whereas Bitcoin has high bid/offer spread and fluctuates 30%+- DAILY. The volatility of bitcoin is far beyond any asset class, while even shares are considered high risk, bitcoin is suicidal
- Shares are completely secure and cannot be stolen, Bitcoin can be stolen by numerous means and are easily lost and unrecoverable if passwords are lost
Bitcoin vs currency
- Currency is relatively stable - £1 might buy 10% less food than last year, but bitcoin has fallen by 90% on several occasions and bitcoin suicides aren't unheard of
- Currency is fast to use - you can pay for things instantly and network such as Visa can support over 45,000 transactions per second, Bitcoin however is capped at FIVE transactions per second, and those wanting their transactions to go through must pay ludicrous fees, and even this will take several hours to confirm
- Currency is backed by the government - the government has a military and tax-collecting powers which underwrite the currency and assure us that it is worth something - there is literally nothing whatsoever underwriting bitcoin, and what utility it once had in supporting drug deals, etc. is now severely undermined by the fees
- Currency is traceable - generally lost currency can be replaced, whereas around 20% of all bitcoin are lost for good, and cannot be replaced. This makes bitcoin completely unsuitable for all but the most hardcore of libertarian anarcho-capitalists, as it's a cinch for the technologically sophisticated to steal it from the technologically less sophisticated. This makes bitcoin unacceptable to all but the sort of person who would say the uninsured health patient should die because they could have got insurance, or the starving should have worked to buy food.
- Currency has low cost - to accept currency via standard means you can expect to pay around 3% in processing fees. However bitcoin not only has ludicrously high fees, the insane volatility means that any business that actually charged in bitcoins would spend most of its income on hedging the ridiculous bitcoin volatility. Hence bitcoin payment processing would actually require you to convert bitcoin to cash immediately which would be far more expensive than currency usage is - certainly over 10%.
In other words it's completely shit and the equivalent of leveraged spread betting.