The difference between an acute accent and a grave accent is in their sound in the spoken word. An acute accent is spoken with a sharp pitch, while a grave accent is spoken with a loud, heavy tone. Each accent marks the stressed vowel of words in several languages. An acute accent is used in languages with Latin, Greek, and Eastern European scripts. A grave accent is used most notably in French, Italian, Norwegian, Catalan, Portuguese, Scottish, and Vietnamese.
Both accents are written as a line or tiny triangle, with the acute accent pointing down on a right to left angle over the letter. The grave accent is physically a mirror image of the acute accent when written out. It points downward at an angle from left to right. Either accent can be a line or a narrow triangle shape. The triangle has the pointed end on the bottom, pointed into the letter, with the base on top, while the line shape is also written more broadly at the top.
The acute accent was first used as a form of pitch accent in Ancient Greece on syllables. The pitch accent describes a sharp sound that dictates the tonal direction of the word. Thus, the modern acute accent is used above vowels to direct the direction and syllabic pronunciation of many words. It is most commonly used to stress high vowels or to elongate a vowel. The acute accent often indicates a rising tone.
The grave accent, also, originated from Ancient Greece, where it was used only to stress the last syllable of a word. It was used to lower the pitch of an acute accent earlier in the word. The grave accent marks the stressed vowel in Italian words, such as città or università. It is used in Italian and other languages as an open vowel sound, marking the height of the vowel. The grave accent has been used to indicate short vowels (in Welsh) and long vowels (in Gaelic), and is characteristic of a low tone, in contrast to acute accents. These low sounds are prominent in many Asian and African languages.
In many world languages, these accents are used to set the difference between homographs, which are words that are spelled the same but mean different things. The homographic words are often set apart simply through the accent, which alters the meaning and pronunciation of the word.
In English, these accents are rare. They are used occasionally in literature to follow a certain rhyming pattern or syllabic structure. The accent can be added to elongate a silent or short letter. They are also common in words borrowed from other languages, such as pièce de résistance. Many computer companies offer keyboards with accents built into the keyboard, whereas other word programs offer shortcuts to inserting these accents when not built into the keyboard.