When I first started learning Drupal, I remember the process of enabling and disabling modules on the Modules page and it took for-ev-er. My laptop was in serious danger of getting hurled across the room, due to my frustration. Then I discovered drush, and downloading and enabling modules was now performed with ease instead of pain and suffering. Of course there's a lot more you can do with drush than just download and enable modules, this is just one example.

I've been using Drush 6.x on my local machine for quite some time now. Poking around Drupal 8's UI and seeing what's new, I haven't missed drush too much...until it was time to test drive a new contrib module for Drupal 8. When I typed into my Terminal window drush dl page_manager, I got quite the error message:

Drush 6.x only works with Drupal 6 or 7. If I wanted to use Drush on my Drupal 8 site, I would need to upgrade to Drush 7.x.