SPARKNOTES
SparkNotes
SparkNotes, originally part of a website called The Spark, is a company started by Harvard students Sam Yagan, Max Krohn, Chris Coyne, and Eli Bolotin in 1999 that originally provided study guides for literature, poetry, history, film, and philosophy. Later, SparkNotes expanded to provide study guides for a number of other subjects, including math, health, physics, biology, chemistry, economics and sociology. SparkNotes does not charge users, but instead uses advertising for revenue.The above text is a snippet from Wikipedia: SparkNotes
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