342 updates on new Breezy

[Albert]

As a new user of Ubuntu, I am still trying to understand what's 
going on.  Immediately upon installing 5.10, I was notified of 
342 updates pending.  I waited until this morning to install 
them.  It appeared to me that everything from the kernel to 
fonts, was updated.  I don't understand how so many packages 
could require updating on a new install.  Would someone please 
explain, or point me to appropriate docs?