Talk may refer to:

A drug, broadly speaking, is any substance that, when absorbed into the body of a living organism, alters normal bodily function. There is no single, precise definition, as there are different meanings in drug control law, government regulations, medicine, and colloquial usage.

In pharmacology, a drug is "a chemical substance used in the treatment, cure, prevention, or diagnosis of disease or used to otherwise enhance physical or mental well-being." Drugs may be prescribed for a limited duration, or on a regular basis for chronic disorders.

The molecules of drugs are complex, and most of them consist of many hydrogen and carbon atoms, a few oxygen atoms, and one or a few nitrogen atoms. Drugs may also have no nitrogen atoms in it and many may have chlorine atoms in it, such as chloral hydrate.

Recreational drugs are chemical substances that affect the central nervous system, such as opioids or hallucinogens. They may be used for perceived beneficial effects on perception, consciousness, personality, and behavior. Some drugs can cause addiction and/or habituation.

Demetria Devonne "Demi" Lovato (born August 20, 1992) is an American singer-songwriter, musician, and actress. Her earliest roles included Angela on Barney & Friends, before she became better known for her starring roles in the Camp Rock movies, as Sonny Munroe in the Disney sitcom Sonny with a Chance, and as the star of the 2009 movie Princess Protection Program. She is also involved in philanthropic activities through charity work and various social and environmental causes.

As a solo musical artist, Lovato released her debut album Don't Forget on September 23, 2008. The album debuted at number two on the Billboard 200 selling 89,000 copies in the first week. It has since shipped over 500,000 copies, earning a gold certification in the United States. Lovato released her second album, Here We Go Again, on July 21, 2009. The album debuted at number one on the Billboard 200, selling 108,000 copies in the first week. Her third studio album, Unbroken, was released on September 20, 2011 and peaked at number four on the Billboard 200. She is working on her fourth studio album.

William Melvin "Bill" Hicks (December 16, 1961 – February 26, 1994) was an American stand-up comedian, social critic, satirist, and musician. His material largely consisted of general discussions about society, religion, politics, philosophy, and personal issues. Hicks' material was often controversial and steeped in dark comedy. In both his stand-up performances and during interviews, he often criticized consumerism, superficiality, mediocrity, and banality within the media and popular culture, describing them as oppressive tools of the ruling class, meant to "keep people stupid and apathetic".

Hicks was 16 years old when he started performing stand-up comedy at the Comedy Workshop in Houston, Texas, in 1978. During the 1980s he toured the United States extensively and performed a number of high profile television appearances. It was in the UK, however, where Hicks first amassed a significant fan base, packing large venues with his 1991 tour. Hicks died of pancreatic cancer in 1994 at the age of 32. In the years after his death, his work and legacy achieved acclaim in creative circles. In 2007 he was voted the fourth-greatest stand-up comic on the UK's 100 Greatest Stand-Ups on Channel 4, and appeared again in the updated 2010 list as the fourth-greatest comic.

Steven David "Steve" Levitt (born May 29, 1967) is an American economist known for his work in the field of crime, in particular on the link between legalized abortion and crime rates. Winner of the 2004 John Bates Clark Medal, he is currently the William B. Ogden Distinguished Service Professor of Economics at the University of Chicago, director of the Becker Center on Chicago Price Theory at the University of Chicago Booth School of Business. He was co-editor of the Journal of Political Economy published by the University of Chicago Press until December 2007. He co-authored the best-selling book Freakonomics (2005) and its sequel Superfreakonomics (2009). He is a grand-nephew of Robert L. May, the lyricist of Rudolph the Red-Nosed Reindeer. In 2009, Levitt co-founded The Greatest Good, a business and philanthropy consulting company. He was chosen as one of Time magazine's "100 People Who Shape Our World" in 2006.

Levitt was born in 1967 and attended St. Paul Academy and Summit School, graduated from Harvard University in 1989 with his B.A. in economics summa cum laude, and received his Ph.D. in economics from MIT in 1994. He is currently the William B. Ogden Distinguished Service Professor and the director of The Becker Center on Price Theory at the University of Chicago. In 2004 he won the John Bates Clark Medal, awarded every two years by the American Economic Association to the most promising U.S. economist under the age of 40. In April 2005 Levitt published his first book, Freakonomics (coauthored with Stephen J. Dubner), which became a New York Times bestseller. Levitt and Dubner also started a blog (www.freakonomics.com). Levitt is an honorary professor at McGill University.