Euler's constant, denoted as γ (gamma), is a mathematical constant approximately equal to 0.57721. It arises in various areas of mathematics, particularly in number theory and analysis. γ is defined as the limiting difference between the harmonic series and the natural logarithm, highlighting its connection to growth rates in sequences. This constant appears in several mathematical contexts, including integrals and series. It is named after the Swiss mathematician Leonhard Euler, who made significant contributions to mathematics in the 18th century. Despite its importance, γ is not as widely known as other constants like π or e.