Smart Quotes, now in its sixth installment, is a small utility to
help you make your documents look more professional, by replacing
quotation marks or other combinations of characters by their more
typographically appropriate versions. If you type a double quote (") or
a single quote (') it will replace it by the appropriate typographically
correct quote (open " or closed " rather than neutral "). It will also
try to correct typos: if you accidentally type "SOmething LIke THis", it
will replace it by "Something Like This". Last, but by no means least,
it can replace short sequences of characters by others, like
Impression's abbreviation facility, which allows you to type ligatures,
accents and other characters  without using the Alt key. It actually
goes further than this, as it can also ensure commas are always before
quotes, remove any extraneous spaces after full stops, etc.