In this chapter, we define the subtraction and division for single valued neutrosophic numbers (SVNNs) which are inverse operations of addition and multiplication for SVNNs, respectively. In addition, we give some algebraic operations for SVNNs and discuss several exceptions which make subtraction and division invalid. After that, we defin the single valued neutrosophic functions (SVNFs) and illustrate their meaning. Subsequently, the concept of neighbourhood for SVNNs is shown, and we utilize \(\varepsilon \) - \(\delta \) rule to study the continuities of SVNFs. Moreover, we present the intermediate value theorem for a class of SVNFs based on their unique properties. Afterwards, we define the derivatives of SVNFs, it is worth mentioning that there are four classes derivatives corresponding to various SVNFs. And we investigate some properties the derivatives have, especially the chain rule which facilitates the calculation of derivatives for SVNFs. Later, we study the differentials of SVNFs and propose the form invariance of differential for SVNFs. Besides, we propose the linear single valued neutrosophic function (LSVNF), and show the process of approximate calculation by utilizing the differential, which is convenient and flexible in some cases of fuzzy evaluation.