A contemporary Bitcoin pockets program can generate many private-keys, every private-key has a public-key. For the commonest transaction varieties, a Bitcoin-address is derived from the public-key.
As you say it’s regular to generate a brand new tackle (i.e. a brand new set of keys) for every transaction. It’s because all of the transaction information is public data – it’s within the replicated journal of transactions we name the blockchain. Anybody can see all transactions for a particular tackle, so if ten individuals every pay you 1 BTC to the identical tackle, they’ll all see that you’ve got acquired 10 BTC in complete at that tackle. This can be a privateness concern. If the addresses are all completely different, they cannot inform which belong to the identical particular person.
Within the Bitcoin community there aren’t any accounts, no digital accounts and no balances.
A pockets can learn via the entire transaction journal and add up all of the unspent quantities in transactions the place the receiving tackle is one for which the pockets is aware of it has the corresponding private-key. That method it may well current a complete quantity to the person. Individuals seek advice from this complete as a steadiness however that is deceptive. The Bitcoin community doesn’t maintain a file of individuals’s balances. The Bitcoin community doesn’t understand how a lot cash anybody has in complete. The US Mint doesn’t know what number of US one-cent cash I’ve sitting in a plastic bag on my shelf, it would not maintain observe of my steadiness or have an account in my title.
The terminology for Bitcoin is a bit muddled. Bitcoin was designed as digital money. Accounts and balances are related to banks, not with piles of greenback payments beneath your mattress or in your leather-based pockets. In case you had been speaking about money within the type of paper cash and steel cash you would not take into consideration accounts and balances. You’d simply wish to know the full sum of money you may have in paper banknotes and steel cash.
Trendy wallets are what known as Hierarchical Deterministic (HD) wallets. From the preliminary personal key (or seed phrase) it’s doable to generate all of the subsidiary keys and addresses in a predictable and repeatable method. You needn’t make a backup of every generated key and generated tackle.