If you’re running infrastructure and applications on AWS then you will encounter all of these things. They’re not the only parts of a network setup but they are, in my experience, the most important ones.
The start of Graham Lyons’ introduction to networking on AWS, which (though the terms may change) is a pretty good primer for networking in any cloud environment. Though cloud infrastructure providers have to deal with things at a different later, Graham’s post covers the basics—VPCs, subnets, availability zones, routing tables, gateways, and security groups—that customers need to manage when assembling their applications.