I recently got an AWS account to experiment with EC2 instances. On my EC2 instance, all I did was to install a MATE GUI and a bunch of other packets to support a VNC server. Then I connected from my personal machine over PuTTy + VNC client to have access to my GUI.

However within 24 hours since I opened my accout I got an email notifying me that I already reached the 1 GB AWS Data Transfer Free tier limit. Can someone help me understand what contributed towards this limit?

Note: I only spent ~10 mins connected remotely to the GUI and about an hour over ssh installing the packets. I also created then immediately terminated a few (~5) EC2 instances during this time.