When I first started on Bitcoin, I saw post that was confusing to me and I think it's also confusing to others who are just starting out
- The Bitcoin wallets do not contain any bitcoins at all
Bitcoin wallets are software to manage your private/public keys (pairs), what you call the *.DAT files
Bitcoin wallets allow you to transfer bitcoins to another address by using a corresponding private key to an address that "contains" bitcoins and sign the transaction and broadcast to the p2p Bitcoin network to the nearest nodes and that propagates throughout the whole network
Most Bitcoin wallets have some nice features like advanced coin controls that allow you to pick inputs. This is particularly useful given the current Tornado dust attack on popular .eth addresses. With a Bitcoin wallet, you can simply send that dust coin to a burn address or never use it as an input
Another feature of a Bitcoin wallet is to utilize RBF, replace by fee, batch transactions, utilize automated generation of change-addresses and other features
I mention all of those things but did you know you can generate a private key by tossing a coin 256 times or using a pair of dice?
Private keys are all you need, because you can work backwards and get your public key using the private key but the reverse is not true
Some people or organization many years ago lost thousands of Bitcoin by writing some custom made scripts, using the private key for test transaction small btc amount, but did not handle the change address, ended up sending the bulk of the btc's as block reward to the to the Bitcoin mining pool that solved the block
Those were the days when the price of btc was low enough, I think the mining pool were able to convince most of the miners to return the btc's, lol. It's been a while I may be misremembering but I think you can still google it
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- All the bitcoins (btc's) are on the blockchain as ledger entries. Even the million bitcoins that belong to Satoshi
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Hot wallet vs cold wallet vs hardware wallet
Cold wallet simply means the private keys are not connected to the internet and hardware wallet is simply a specialized computer that is not running Windoze and cannot get a virus
That's why I said if you dedicate an old laptop/computer, install Bitcoin core, put a long password (
make sure you test that the password is good), disconnect from the internet, put it in a faraday cage if you wish
When you fire up the Bitcoin core software, you can generate 100 public addresses (the private keys won't be visible to you unless you explicitly issue the command), copy those
public addresses to a text file send some test btc's to them
Backup the *.DAT file(s), put in encrypted volume, encrypt the volume again, encrypt it again, you can encrypt it as many times as you wish, you can generate hidden volumes using some sophisticated encryption software. There you go, you have a cold wallet 100 addresses that are never connected to the internet
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- Many bitcoins have been lost because the owners secured the private keys too much to the point they can never be recovered