Notice: Over the next few months, we're reorganizing the App Engine documentation site to make it easier to find content and better align with the rest of Google Cloud products. The same content will be available, but the navigation will now match the rest of the Cloud products.
App Engine offers you a choice between two Python language environments. Both
environments have the same code-centric developer workflow, scale quickly and
efficiently to handle increasing demand, and enable you to use Google’s proven
serving technology to build your web, mobile and IoT applications quickly and
with minimal operational overhead. While the two environments have a lot in
common, they differ in a few important ways.