Video

Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media.

Video systems vary greatly in the resolution of the display, how they are refreshed, and the rate of refreshed, and 3D video systems exist. They can also be carried on a variety of media, including radio broadcast, tapes, DVDs, computer files etc.

History

Video technology was first developed for Mechanical television systems, which were quickly replaced by cathode ray tube (CRT) television systems, but several new technologies for video display devices have since been invented. Charles Ginsburg led an Ampex research team developing one of the first practical video tape recorder (VTR). In 1951 the first video tape recorder captured live images from television cameras by converting the camera's electrical impulses and saving the information onto magnetic video tape.

Video recorders were sold for $50,000 in 1956, and videotapes cost $300 per one-hour reel. However, prices gradually dropped over the years; in 1971, Sony began selling videocassette recorder (VCR) decks and tapes to the public.

Compound interest

Compound interest is interest added to the principal of a deposit or loan so that the added interest also earns interest from then on. This addition of interest to the principal is called compounding. A bank account, for example, may have its interest compounded every year: in this case, an account with $1000 initial principal and 20% interest per year would have a balance of $1200 at the end of the first year, $1440 at the end of the second year, $1728 at the end of the third year, and so on.

To define an interest rate fully, allowing comparisons with other interest rates, both the interest rate and the compounding frequency must be disclosed. Since most people prefer to think of rates as a yearly percentage, many governments require financial institutions to disclose the equivalent yearly compounded interest rate on deposits or advances. For instance, the yearly rate for a loan with 1% interest per month is approximately 12.68% per annum (1.01¹² − 1). This equivalent yearly rate may be referred to as annual percentage rate (APR), annual equivalent rate (AER), effective interest rate, effective annual rate, and other terms. When a fee is charged up front to obtain a loan, APR usually counts that cost as well as the compound interest in converting to the equivalent rate. These government requirements assist consumers in comparing the actual costs of borrowing more easily.

Khan Academy

Khan Academy is a non-profit educational organization created in 2006 by educator Salman Khan with the aim of providing a free, world-class education for anyone, anywhere. The organization produces short lectures in the form of YouTube videos. In addition to micro lectures, the organization's website features practice exercises and tools for educators. All resources are available for free to anyone around the world. The main language of the website is English, but the content is also available in other languages.

History

The founder of the organization, Salman Khan, was born in New Orleans, Louisiana, United States to immigrant parents from Bangladesh and India. After earning three degrees from the Massachusetts Institute of Technology (a BS in mathematics, a BS in electrical engineering and computer science, and an MEng in electrical engineering and computer science), he pursued an MBA from Harvard Business School.

In late 2004, Khan began tutoring his cousin Nadia who needed help with math using Yahoo!'s Doodle notepad.When other relatives and friends sought similar help, he decided that it would be more practical to distribute the tutorials on YouTube. The videos' popularity and the testimonials of appreciative students prompted Khan to quit his job in finance as a hedge fund analyst at Connective Capital Management in 2009, and focus on the tutorials (then released under the moniker "Khan Academy") full-time.

Cars (film)

Cars is a 2006 American computer-animated comedy-adventure sports film produced by Pixar Animation Studios and released by Walt Disney Pictures. Directed and co-written by John Lasseter, it is Pixar's final independently-produced motion picture before its purchase by Disney. Set in a world populated entirely by anthropomorphic cars and other vehicles, it features the voices of Owen Wilson, Paul Newman (in his final non-documentary feature), Larry the Cable Guy, Bonnie Hunt, Tony Shalhoub, Cheech Marin, Michael Wallis, George Carlin, Paul Dooley, Jenifer Lewis, Guido Quaroni, Michael Keaton, Katherine Helmond, and John Ratzenberger. Real life race car drivers Dale Earnhardt, Jr., Mario Andretti and Michael Schumacher, and car enthusiast Jay Leno (as "Jay Limo") voice themselves. It is also the second Pixar film—after A Bug's Life—to have an entirely non-human cast. The film was accompanied by the short One Man Band for its theatrical and home media releases.

Cars premiered on May 26, 2006 at Lowe's Motor Speedway in Concord, North Carolina and was theatrically released on June 9, 2006, to positive reviews. It was nominated for two Academy Awards, including Best Animated Feature, and won the Golden Globe Award for Best Animated Feature Film. The film was released on DVD on November 7, 2006 and to Blu-ray Disc in late 2007. Related merchandise, including scale models of several of the cars, broke records for retail sales of merchandise based on a Disney·Pixar film, bringing an estimated $10 billion in 5 years since the film's release. The film was dedicated to Joe Ranft, who was killed in a car accident during the film's production.

Interest

Interest is money paid by a borrower to a lender for a credit or a similar liability. Important examples are bond yields, interest paid for bank loans, and returns on savings. Interest differs from profit in that it is paid to a lender, whereas profit is paid to an owner. In economics, the various forms of credit are also referred to as loanable funds.

When money is borrowed, interest is typically calculated as a percentage of the principal, the amount owed to the lender. The percentage of the principal that is paid over a certain period of time (typically a year) is called the interest rate. Interest rates are market prices which are determined by supply and demand. They are generally positive because loanable funds are scarce.

Interest is often compounded, which means that interest is earned on prior interest in addition to the principal. The total amount of debt grows exponentially, and its mathematical study led to the discovery of the number e. In practice, interest is most often calculated on a daily, monthly, or yearly basis, and its impact is influenced greatly by its compounding rate.