Greek words are usually printed with one of three accents: acute ( ´ ), grave ( ` ) or circumflex ( ῀ ). You will meet them in dictionaries and printed texts, so it is important to be able to recognise them. But they can be ignored in the early stages of learning Greek, except on rare occasions where they affect the meaning of a word. From this point in the course, Greek words will be displayed with accents.
The following statement contains a grave, an acute, and a circumflex, in that order:
χεὶρ νίπτει χεῖρα
cheir niptei cheira = a hand washes a hand (or, ‘one hand washes the other’)
The system of accents was devised in antiquity, probably around 200 BCE at the great library of Alexandria in Egypt. Its purpose was to help readers pronounce Greek syllables with the correct melodic ‘pitch’, that is with a rising tone (acute), a falling tone (grave) or a rising followed by a falling tone (circumflex), similar to that found in modern tonal languages like Chinese. Since syllables in English are not expressed with pitch, but with stress, i.e. a greater or lesser degree of emphasis, accents are difficult for native English speakers to use as intended. They are typically reserved for more advanced students of Greek, who may find them of great interest.
Learners are rarely asked to use accents in the early stages of studying ancient Greek. For the present, concentrate on mastering the alphabet and breathings. And try not to confuse breathings with accents.