Panels embody the spirit of Drupal: make it easy to re-use content in visually appealing layouts, and to separate the Model (data) from the View (layout) so that you can easily change them.
Rather than heavily customizing a theme to get a layout, and having to hack in to have different themes (3 column home page, 2 column other pages) you can choose a Layout (and even customize HTML/CSS for it!)
download modules: panels, jquery_ui, ctools
http://drupal.org/project/panels http://drupal.org/project/jquery_ui http://drupal.org/project/ctools
extract them into the directory /sites/all/modules
download the jquery zip: http://code.google.com/p/jquery-ui/downloads/list?q=1.6
extract it to have /sites/all/modules/jquery_ui/jquery.ui-1.6/
Rename the sub-directory into "jquery.ui" within the jquery_ui module folder:
enable all of the above modules via: admin > site building > modules setup any content editor roles: admin > user management > permissions
Now to create some test panels: admin/build/panels (aka admin > site building > panels)
New Panel Page -> title, name, path all = test > Continue LAYOUT 1 column (continue) rename Administrative Title from Panels to test (continue) Title = test (continue) Update and Preview SAVE
Now you can view your newly created Panel Page using http://domain.com/test Click on Edit Panel (this will take you back to ) admin/build/pages/nojs/operation/page-test/handlers/page_test_panel_context/content
Click on the Gear symbol (left of Middle Column) -> Add Content
Here's where you can add an existing node or custom content
You can also Change Layout...
Depending on the layout (3 column, flexible, etc.) and what content you use (existing nodes, custom content, nodes created by panels with custom css) you can have a huge variety of presentation of your content.
not always obvious, but click SAVE when changing layout (on the very bottom)!
If you want panels inside of panels or Panels used as a Block then you'll need to explore admin/build/panels > "Mini Panels"
To remove the Panel Page Title then choose the No Title dropdown For Panel Content - leave the Title field blank (it will appear as No Title) *You can choose a "custom style" which includes rounded shadow box & colors! (Color tool or Hex and the Preview button means you can accent/match your theme)