A unit fraction is a type of fraction where the numerator is always 1, and the denominator is a positive integer. For example, 1/2, 1/3, and 1/4 are all unit fractions. They represent one part of a whole that is divided into equal sections. Unit fractions are fundamental in understanding how fractions work and are often used in various mathematical concepts. Unit fractions can be added together to form other fractions. For instance, 1/4 + 1/4 equals 2/4, which simplifies to 1/2. This property makes unit fractions useful in teaching basic arithmetic and fraction operations. Understanding unit fractions lays the groundwork for more complex fraction concepts in mathematics.