Summary Deriving from the phenomena that the Arabic language needed So she added to it a much-needed linguistic balance over time and over the years and thus contributed to preserving its continuity, growth, ease of use and pronunciation, and employing its words in all that needs it.The issue of derivation and its importance to language is one of the topics that linguists have fought in, in the past and present, among them by way of mentioning but not limited to: Ibn Jani, Ibn Faris, Al-Thaalabi, Al-Suyuti, Ibn Ashour, Tamam Hassan, and others who do not have enough room to mention them.The nature of this research necessitated that it be divided into a group of titles, namely:1- The meaning of the derivation is a language and a convention.2- The opinions of the ancients and the moderns on the derivation.3- Types of derivation.Then the search was concluded with a set of results, including : 1-Derivation reveals to us the link between molecules and faculties, or partial meanings and total meanings. 2-The importance of derivation lies in clarifying the origin from which words branched out or from which they were built. 3-Derivation is a prominent feature of the Arabic language and is one of the means of its growth, given the role of derivation in the birth of Arabic expressions. 4-Derivation has an important role in knowing the original word from the extraneous word or the Arabic word, because the world often remains isolated and you do not have an origin to refer to. 5- Derivation has its types, including: the large, the largest, the small derivation, and then the sculpture, which the researcher believes is the best way to keep up with the tremendous development that life is witnessing today.