In Drupal 8, we've significantly improved the way pages are rendered. I will explain the entire render pipeline, which will also cover:

render caching — blocks and entities are now render cached automatically!
cache tags — finally we have the cache invalidation system we've always needed!
assets — only the necessary assets are loaded anymore, thanks to asset dependencies!
bubbling — rather than relying on global statics that broke caching, we now correctly bubble up all attached metadata — no more frustrations!
But I will also explain what is going to be possible in Drupal 8:

anonymous page loads: invalidating Varnish/CDNs with perfect precision
authenticated page loads: not completely regenerated on every page load, but assembled from render cached parts
alternative render strategies, like Big Pipe
Where relevant, I'll compare with Drupal 7, how you can write Drupal 7 code today that will be easy to upgrade to Drupal 8, and which Drupal 7 backports exist (hint: Big Pipe does exist!).

This talk provides a comprehensive overview about the finalized Drupal 8 render pipeline!