HI or Hi may refer to:

• Hello, a greeting in the English language
• Hi (kana), Japanese character
• Hi (magazine), teen lifestyle publication
• Hi (Ofra Haza song)
• Hi, a character in the comic strip Hi and Lois
• Hi Records, in music, a Memphis soul and rockabilly label
• Hi River, also known as the Ili River, in northwestern China
• Hindi, an Indo-Aryan language by ISO 639-1 language code
• Hydrogen iodide, in chemistry, a diatomic molecule
• Hi, mobile phone brand of Dutch company KPN

Hello is a salutation or greeting in the English language. It is first attested in writing from 1833.

Hello (stylised as HELLO!) is a weekly magazine specialising in celebrity news and human-interest stories, published in the United Kingdom since 1988. It is sister magazine to ¡Hola!, the Spanish weekly magazine launched in Spain in 1944. ¡HOLA! Spanish, Hello UK, and ¡HOLA! Mexican – launched in 2006 – make up the magazines published by HOLA, S.A and distributed in over 100 countries. Local editions of the magazine are also published in Argentina, Bulgaria, Canada, Colombia, Dominican Republic, Ecuador, Estonia, Greece, India, Indonesia, Malaysia, the Middle East, Morocco, Nigeria, Pakistan, Peru, Puerto Rico, Russia, Serbia, Thailand, Turkey and Venezuela.

The University of Iceland is a public research university in Reykjavík, Iceland, and the country's oldest and largest institution of higher education. Founded in 1911, it has grown steadily from a small civil servants' school to a modern comprehensive university, providing instruction for about 14,000 students in twenty-five facilities. Teaching and research is conducted within social sciences, humanities, medicine, natural sciences, engineering and teacher education. It has a campus concentrated around Suðurgata street in central Reykjavík, with additional facilities located in nearby areas as well as in the countryside.