How to access HTTP server on Amazon EC2?

Question

Amazon Web Services

Hello!
Got myself an Amazon EC2 instance. I can easily connect to it via SSH via putty, but I cannot access the HTTP server, which I start with the command:
sudo python -m SimpleHTTPServer
Then I try to open http://public_dns:8000 in the browser and Connection Timeout crashes.
Also, neither Public IP nor Private IP is pinged.
I tried to make
sudo ufw disable
and enable HTTP in the instance settings (Security Groups-> Add inbound Rule->HTTP), but it did not help.
The fact is that I am not very versed in network technologies, and therefore I do not understand the difference between Public IP, Private IP and Public DNS - why do I need it?

Answer 1

Go to security group
and open port 8000

Answer 2

You may not have set the Outbound Rule.
IMHO, if you are not very versed in network technologies, then open all traffic on the instance (for all ports too), see how it works, and then leave only what you need.