Help me understand themes with sidebars and how to populate the sidebar from drupal BACKGROUND

I'm converting a static html site to drupal.   We have some pages that have content and a sidebar and some pages that just have content without a sidebar.

I plan on simply adding a new field called 'sidebar' to the article and base page content types.  I can then modify the theme to render this field.

QUESTION 

Is their any reason why adding this new sidebar field to the content type is considered bad practice?

If I want to place a block in the sidebar region it could simply be after or before the data entered into the sidebar field correct?

I'm a total newbie to drupal,  I understand these are basic question but I couldn't find a definitive answer on the web regarding this.

Thanks
In Drupal, themes have regions. The sidebars are regions, just like the header, footer, conternt etc regions. Over simplifying a bit, content is places in blocks, then the blocks are placed in the regions, and changing the theme usually requires the blocks to be allocated again. Fields are part of the content, not the theme. There is no 'sidebar field'.

I would suggest that you set up a drupal test-bed, and play with it for a while before you take the leap of trying to migrate a site. Drupal is powerful, but there is no way to bypass the learning curve. You need to roll up your sleeves and work with it for a while.

Good luck.