Simple and effective C++ matrix-vector library for nonprofessionals in computer science. This paper presents a matrix-vector computational library written in the C++ language. Effective matrix-vector manipulation is an essential aspect of scientific numerical modeling, especially while using the finite element method. Even though there are a lot of matrix libraries written in C++ which are freely or commercially available on the Internet, most of them are either too complicated or too simple, i.e. with very limited capabilities. Therefore, the main idea is to develop a reliable matrix library, as part of the computer code in C++, which will be, at the same time, as simple as possible and as complex as possible. Consequently, the basic motto of the library, which is called SMV++, is “Simple and effective” and it is meant to be of use to researchers dedicated to reliable obtained results and not to the “beauty of programming”. The library is developed without use of the template concept and inheritance, with the purpose of understanding it easily and of extending it easily with new possibilities and algorithms. Last but not least, it is aimed at having a simple and intuitive user interface. The bottom line is that the SMV++ is not meant to be of use to someone who is in the software development business. Rather, it is oriented to the user who has a modest programming knowledge (e.g. a Ph.D. student) and who is basically concerned about how to obtain the solution to the considered problem, for which he has to do some “homemade programming”, because the available commercial software cannot be applied for all of his/her needs. Consequently, as mentioned, the motto of the library is “Simple and effective”; the effectiveness is in the sense of complexity of possibilities, rather than computational efficiency. However, if one is forced to choose between the two in the development of the library, having in mind the target users, priority is given to simplicity of use.