Amazon EC2

Amazon EC2 stands for Elastic Compute Cloud and is not a single service but should be thought of as many services running as one; think of EC2 as Infrastructure as a Service

Amazon EC2 mainly consists of the following:

Renting virtual machines (EC2)
Storing data on virtual drives (EBS)
Distributing load across machines (ELB – Elastic Load Balancer)
Scaling the services by leveraging an auto-scaling group (ASG – Auto-Scaling Group)Understanding EC2 is fundamental to knowing how the cloud works

When creating an EC2 instance a user will need to make the following decisions:

What operating system will be installed on the instance – The current available options in AWS are: Linux, Mac OS and Windows
How much processing power will be required (CPU / Cores)
The amount of RAM the instance will require
Storage space required for the instance – Network attached storage such as EFS and EBS or actual hardware (EC2 Instance Store)
Networking such as the type and speed of the network card and IP addresses
Security group and Firewall rules
Any EC2 User Data scripts which will be execute the first time that the instance is powered on. Use the EC2 User Data Script to install software, install updates, download information from the Internet etc.

Note that the EC2 User Script runs as the Root User