Accents

What are the accents for anyway?
Accents have three main purposes:
1) Change the Sound
2) Change the Meaning
3) Denote an Etymological Change from Latin

Referring to accented characters

é
è
ë

ì
î
ï
ò
ô
ù
à
â
ç

Acute Accent - L'accent aigou
The acute accent (l'accent aigu) only appears above the letter e- é. Without the acute accent, the the letter e is normally pronounced [ε] or [ә]. With the acute accent it is pronounced [e] (see Vowel Sounds I).

Dieresis - Le tréma
The dieresis marks a vowel as being in a separate syllable from any neighboring vowel. For example the letter combination ai is normally pronounced [e] or [ε] . However with the dieresis over the i, it becomes [ai].

maïs
astéroïde
haïr
corn
asteroid
to hate

égoïste
Noël
coïncidence

selfish
Christmas
coincidence

Grave Accent - L'accent grave
In most cases the grave accent (l'accent grave) has no effect on the pronunciation of a vowel. It is placed over the letter e when the next syllable is mute.

mère
très
secrète
mother
very
secret
je mènerais
ils conquièrent
I would lead
they conquered

It is also placed over a and u in a small number of words:

à
au delà
to
beyond
voilà

where

In a few cases, the grave accent serves to distinguish two words which otherwise would have the same spelling.

where ou or

There are a few cases when the grave accent does affect pronunciation - at least in some regions. In certain word endings, when it appears over the letter e, it causes the final syllable to be pronounced as [ε] as opposed to [e] (ie. dès vs des). (see Vowel Sounds I). This is true mostly for the northern region of France.

Circumflex - Le circonflexe
The circumflex, or the hat (î, â, ê) has no direct effect on pronunciation, but may indicate a slight change in sound between two words with similar pronunciation: mal [a] (bad) vs, le mâle [α] (male), les pattes [a] (paws) vs. les pâtes [α] (pasta); notre [o] (our) vs. le nôtre [ɔ] (ours).  All those advocating reform of the writing system are unanimously in favor of getting rid of it. There really aren't that many words that have the circumflex. Sometimes the circumflex marks the site of a lost s which existed in the original Latin version of the word, but over the centuries, as the language evolved and changed, was eventually dropped. English words that share the same Latin ancestor normally still have this s.

maître
pâte
bête
master
paste
beast
île
hôte
island
host

Cedille - La cédille
The cedille, is the only accent used on consonants in French.  It only apprears on the letter c and forces the c to be a soft [s] sound instead of a hard [k] sound when followed by the back vowels: a, o, and u. Otherwise, the cedilla is not needed because the c is always sofr when followed by the front vowels: e and i.

garçon
leçon
ça
boy
lesson
that

commande
campus

order
campus