Mastering Intellij IDEA and Android Studio

IaaS is the layer of cloud computing where you rent raw infrastructure through an API, meaning virtual machines, disks and networks, and take responsibility for the operating system and everything you install above it.

PaaS is a hosting layer that takes your source code and turns it into a running application for you, owning the machines, the runtime, the build, the routing, the certificates and the restarts, so that shipping becomes a push rather than a project.

Serverless computing runs your code only while an event is calling it: the provider conjures an execution environment on demand, throws it away afterwards, and charges for work performed instead of for capacity sitting idle.

Load balancing is the practice of putting one entry point in front of several interchangeable servers and distributing incoming requests among them by a chosen policy, so that no single machine carries the traffic and no single machine's failure takes the service down.

A CDN is a worldwide network of servers that answers requests for your site from a location near the person asking, instead of sending every request back to the single machine your site runs on.

DNS is the distributed lookup system that turns a hostname such as getting-digital.net into the IP address a browser can connect to, by walking a chain of nameservers whose answers are then cached for a lifetime the domain's owner publishes.

Microservices is an architectural style in which one application is built as a set of small services, each running in its own process, owning its own data and talking to the others over lightweight network calls, so that each can be built, deployed and scaled on its own.

Continuous integration is the practice of every developer merging their work into a shared mainline at least once a day, with an automated build and test run on each merge, so that integration problems surface within minutes of being created rather than weeks later at release time.

Unit testing is the practice of writing small automated checks that call one piece of code in isolation, a function, a class or a module, with known inputs and assert on its outputs, so that a change which breaks that behaviour fails a test within seconds of being made.