I'm a bit new to Bitcoin.
I just downloaded a Bitcoin wallet "bitcoin core". And I have downloaded all the nodes (a lot of data, I believe it's the complete one).
When I click the "Receive", I can request money.
But I noticed that every request, I'm assigned a different address. Then I noticed that it's an official recommendation by the software.
Is there any reason for that? How many addresses can I have? What do I need to be prepared if I have a lot of address? (for instance, to backup something)