The different layers of English vocabulary allow to speak or write differently to different people in different situations or contexts. The main division in registers is between formal (used to speak to people in the wider world of society) and informal (used to speak to family and friends). As the informal register includes the colloquial, slang and dialectal registers, the formal embraces all the rest. In current trends of modern English semi-formal language appears, mainly in advertisements, when people want to attract somebody. The choice of register adapts the person we are addressing and the situation or context we find ourselves in. Formality cannot be equated with politeness. In certain situations being formal might seem rude and aloof.