There's no names or addresses involved, is there?

Lets say you and I trade bitcoins. I give you my address for you to send me some btc, now you have my address. You can now go to the blockchain.info site and look at all my previous and future transactions even if I move them to different wallets, someone can always track your coins, is that correct?

My main concern is, that I don´t want people who I trade with or anyone else finding out how much BTC I have. How do I prevent this?

There's initial anonymity. But you're right in that if someone wants to find out who's transacting what there's a lot of information available. This is part of the reason why people insist on using cold wallets (and multiple wallets), it makes it harder to track the person who originated the transaction.

First of all, bitcoin is pseudonymous, not anonymous. This means that you don't know exactly who the other person is, but you have someway to identify them.

Secondly, blockchain.info does not give you the ip address of the person. It only gives you the ip address of the node that relayed the transaction to them, which is most likely not the person that sent the transaction. It is very difficult, next to impossible, to determine the ip address of the node that created the transaction.

Thirdly, you should not be reusing bitcoin addresses. By keeping your addresses separate for each transaction, then whoever is sending you Bitcoin will only know that you have at least the amount they sent you. They don't know how much you actually have. Services who also use new addresses for every transaction also protect your anonymity since others won't know who owns that new address. It could be your own wallet, your friend's, or that porn site you pay for.

There are also some services that can help you anonymize like mixers or CoinJoin transactions.

No. If you send again from that wallet, without receiving any more bitcoin, you will be sending from the first address. The Bitcoin cannot magically move from one address to another, even in a wallet since the wallet is just an easy way to keep all of your addresses in the same place. There is no difference between a sending and receiving address, there is just only a Bitcoin address, which can be sent to and from.

Bitcoin is anonymous as along as you do not let others know some addresses belong to you. Monero is an anonymous coin by design. It is not traceable.

Yeah. I don't really know where you found the IP addresses and names. I had a look on blockchain and I couldn't find any of these 2 things. The only thing that I can do is find the account balance and the account transaction history. That is kind of dangerous as people can find the best hacking targets.(The accounts with high balance)

I quote that. Mixing your coins can be a long process if you want some anonimity but that's the way. And as altcoinhosting said, whenever you'll use them they will be linked to you. But of course you can clean them quite well.

There are even ways to circumvent this, like anonymous PO boxes or remailing services... But, for me, using such services is overkill... Escpecially if you're not doing anything illegal.

That's why it's kinda difficult if you want to buy a physical thing with Bitcoin but you also want to keep your anonimity safe.