If you set up a poll on your Drupal site and intend to get votes from both anonymous visitors as well as from authenticated users, you need to make sure that "vote in poll" action is permitted for them.

To do this, go to Administer -> Permissions and scroll down to poll settings.

In the same way, search action is also disabled by default. So you if want visitors to your site to be able to search for content, then you need to enable it.

I recently enabled caching in a Drupal site and could notice improvement in page-loading performance. Drupal can be compute-intensive, so a cache goes a long way in making your site more responsive to visitors.

There are a few options to choose from when you enable cache. One of them is the 'Minimum cache lifetime.' This defaults to '' and I think it does so for a good reason. With this setting, any time you post a content, all cached pages that are affect by that post expire immediately, so you can the effect of the post right away.