shell - Difference Between localhost 8888 and 8890

Question

I was wondering what the 8888 and 8889 number means when I launch a jupyter notebook in my browser (I'm launching the notebook via Anaconda Navigator). I noticed how the number increases by 1 (from 8888 to 8889, to 8891) as I launch more notebooks from my anaconda navigator, but the files I have access to are exactly the same. Why then have different numbers?

Thank you!

Answer 1

You are launching a new process which uses an unused port. The first start will use port 8888, the second (if the process is active) will use port 8889 and so on.

Note: this is just for Jupyter. Other applications may exit with an error code stating the "port is already in use".