Performance is everything. Load time is one of the most crucial aspects in getting users or prospective clients to use your website. If your site takes minutes to load then no matter how useful your site may be no one will use it. The impatience of users has only shortened in recent years as the web has become a platform to share and use content.
Check Your Site
Loading Your Site More Efficiently
Boost is a great tool for speeding up Drupal performance, especially in shared hosting environments. However, you should be relatively familiar with Drupal in order to use it since it can be a chore to set it up properly. If you are using Drupal 7 you will need to have clean urls on, as well as, access to your .htaccess and robots.txt file ino refer to get Boost to work. Boost works by skipping the Drupal/PHP/MySQL process and serving HTML or HTML.gz files. The one drawback is that Boost works for anonymous users and there are other modules that can be used, but only if you have access to do some server-side changes.
Another option is to serve the bulk of your images and scripting from another server. The CDN module is a way to give Drupal 7 the ability to serve content from a CDN server. though like with most modules you will need a bit of experience with CDNs in order to set this up.
Each of the ones below require that you have access to modify files on your server. If you are using a shared hosting environment then you will be out of luck.