Elastic Compute Cloud(EC2) – This is the core compute platform provided by AWS. If offers unmatched scalability and configuration options along with dynamic pricing and great uptime. This is a fully self managed service and you can customize security and the server config to suit your application needs.
Relational Database Service(RDS) is a platform as a service provided by AWS that offers numerous database engines like MySQL, MSSQL, Oracle & MariaDB on the AWS platform. Again high availability and scalability are at the core. Many configuration and backup options along with security groups make it a great choice.
Amazon CloudWatch is the monitoring service offered by AWS for all the services across its platform. It offers detailed dashboards and customized alarms that can be configured to trigger email alerts.
Route 53 is a DNS routing system offered by Amazon that can be used to created hosted zones within AWS and manage the traffic to your EC2 instances.
AWS Lambda offers a serverless computing service. It lets you an run your trigger based application without worrying about the scale. Many coding platforms like Node.js & Java are supported making the learning curve very smooth.