Hello DanielHamilton,
thanks for your answer!
I don't understand your logic.
If 0.01 BTC is worth 4, and outputs that are lower than 0.01 BTC, might incur a transaction fee. then you cannot make micropayments of less than 4 with Bitcoin without having a transaction fee of at least 0.0001 BTC (worth about 0.04)
I just wanted to get confirmed, that this "lower than 0.01 BTC incurs a fee of at least 0.0001" is correct, cause
that means Bitcoins is not very well suitable for payments up to 4.
No. Transaction size is also increased by receiving multiple small values of bitcoins that must then be spent together as inputs to a transaction.
Thanks for this valuable information

. So for transaction size,
it's always better to receive bitcoin in a larger one-time transaction rather than many more transactions. Because if you want to send the bitcoin away again and the bitcoin, that you are trying to send, came from multiple transactions, the transaction size will get bigger...
The transaction is still immediate, but the confirmation may take a while (possibly several days). Under some circumstances where the transaction looks like spam or a DDOS attack on the network, many peers may refuse to relay the transaction. In this case your recipient will not see the transaction, and neither will the miners.
This means that it is possible to send Bitcoin to someone else,
without him ever noticing that he has received Bitcoins. That means it is actually possible to lose Bitcoins in the sending process, even though the correct Bitcoin address has been named.. right? I find that very strange. If I'm using a program such as MultiBit, will it tell me when I should pay a transaction fee? Will it recommend me to pay a transaction fee for small amounts? Or how is this done. And how is this done in automatic scripts? Does one usually define that payments lower than 0.01 BTC are subject to transaction fee of 0.0001? And
how do you define in a transaction what part of the transaction is designated as transaction fee and what part of the transaction is for the actual receiver?