Serif Vs Sans-serif

The difference between serif and sans-serif fonts are that sans-serif fonts don't use
flourishes, tails or flags. A serif font uses tails and is generally more decorative. Most
people see the serif fonts as more readable, the reason for this is they see them as similar
to handwriting. Serif fonts as mostly used in the body section of printed works like a
magazine or book.
Most content on the web uses serif-fonts like Arial or Verdana the same can be said for the
header of printed documents. With larger print I think it is best to use sans-serif as they are
easier to read. The main consideration in design is that you want the reader or
viewer to be able to read the message not the font.