notice of change of address
The notice you give Skatteverket when you move to a new address in Sweden, so that the population register shows where you actually live. You do it online on Skatteverket's website; the register then tells other agencies, and post addressed to you follows.
Your registered address decides which municipality and region you belong to, and so where you pay tax, which health centre and schools you are offered, and where official letters, such as your tax return, are sent.
Skatteverket also sends a letter to the people already registered at the address, and you can ask it to block changes of address made in your name that you did not make yourself.