We'll look at the basic HTTP caching we've been using for decades, and outline two strategies for success:

• Immutable Content - Where content at a URL never changes,
• Mutable Content - Where we rewrite content at URLs, and rely on Last-Modified or ETag headers to detect modifications.

We'll go over the basics of the first widely-applied technology for building offline-capable web apps. Appcache is known for its temperamental behavior, and its ability to almost solve the problems we need it to solve. We'll review a strategy for minimizing risk and maximizing benefit -- ultimately delivering a fast return-visit experience for those browsers that don't yet support more modern approaches.

We'll add an Appcache Manifest to our single page app, allowing browsers to download the complete application in the background on users' first visit.

Service workers are programmable network proxies that can be installed on our users' browsers. Rather than providing us with a turnkey solution to the "offline problem", service workers expose a set of primitives that we can use to build our own solution. We'll dive deep into the worker registration process and lifecycle, discuss several different categories of resources, and provide an optimal caching strategy for each category!

Break for Lunch

We'll apply our newfound knowledge of service workers, in order to greatly improve the "time to first paint" and "time to interactive" of our app for return visits.