The fundamental frequency is another name for the first harmonic.
It is the frequency's lowest possible value. In layman's terms, the first harmonic is a wave with only two nodes and an antinode.
The fundamental frequency is the lowest feasible frequency at which the string can vibrate in order to generate a standing wave pattern.
The string's length is specified as where is the string vibration's wavelength (wave).
The first harmonic's frequency is listed as Where is the wave's speed and is the length of the string.
The first harmonic has the following properties: The initial harmonic will contain only half of the wave. The distance between the antinodes of the first harmonic is equal to half the wavelength of the string vibration (wave). Again, in the instance of the first harmonic, the length of the air is equal to half the value of the string vibration's wavelength (wave).
Thus, the fundamental frequency is the lowest feasible frequency at which the string can vibrate in order to generate a standing wave.