Fundamental may refer to:

• Fundamental frequency,a concept in music or phonetics, often referred to as simply a "fundamental".
• Fundamentalism, the belief in, and usually the strict adherence to, the simplistic or "fundamental" ideas based on faith of a system of thought.Interestingly not based on the fundamental principles or objectives of a system. i.e. following the word and not the spirit of a law or system.
• Any of a number of fundamental theorems identified in mathematics, such as
  • The fundamental theorem of algebra, a theorem regarding the factorization of polynomials.
  • The fundamental theorem of arithmetic, a theorem regarding prime factorization.
• Fundamental analysis, a method that uses financial and economic analysis to predict the movement of security prices such as bond prices, but more commonly stock prices.

In music:

• Fundamental (Bonnie Raitt album)
• Fundamental (Pet Shop Boys album)
• Fundamental (Puya album)
• Fun-Da-Mental, a rap group.

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