A resident of Chennai is called a Chennaiite. As of 2001, Chennai city had a population of 4.34 million, while the total metropolitan population was 7.04 million. The estimated metropolitan population in 2006 is 4.5 million.In 2001, the population density in the city was 63,926 per mi, making it one of the most densely populated cities in the world. The average literacy rate is 80.14%, much higher than the national average of 64.5%. The city has the fourth highest population of slum dwellers among major cities in India, with about 820,000 people (18.6% of its population) living in slum conditions. In 2005, the crime rate in the city was 313.3 per 100,000 people, accounting for 6.2% of all crimes reported in major cities in India. The number of crimes in the city showed a significant increase of 61.8% from 2004.
Chennai is a major centre for music, art and culture in India. The city is known for its classical dance shows and Hindu temples. Every December, Chennai holds a five-week long Music Season celebrating the 1927 opening of the Madras Music Academy
Among Chennai's festivals, Pongal is celebrated over five days in January, is the most important. Almost all major religious festivals such as Deepavali, Eid and Christmas are celebrated in Chennai. Tamil cuisine in Chennai includes vegetarian and non-vegetarian dishes. Many of the city's restaurants offer light meals or tiffin, which usually include rice-based dishes like pongal, dosa, idli and vadai,
Chennai has a tropical climate, specifically a tropical wet and dry climate. The city lies on the thermal equator and is also on the coast, which prevents extreme variation in seasonal temperature. The weather is hot and humid, for most of the year. The hottest part of the year is late May to early June, known locally as Agni Nakshatram ("fire star") or as Kathiri Veyyil, with maximum temperatures around 38–42 °C (100–108 °F). The coolest part of the year is January, with minimum temperatures around 18–20 °C (64–68 °F). The lowest temperature recorded is 15.8 °C (60.4 °F) and highest 45 °C (113 °F). The average annual rainfall is about 51 in. The city gets most of its seasonal rainfall from the north-east monsoon winds, from mid-October to mid-December. Cyclones in the Bay of Bengal sometimes hit the city. The highest annual rainfall recorded is 2,570 mm (101 in) in 2005.