In the era of the rapid development of the terrestrial laser scanning technology (TLS), that facilitates the acquisition of large data volumes in the form of three-dimensional point clouds, a need arises to create modern solutions to enable effective and efficient data processing. This paper presents the PCL (Point Cloud Library). This is an Open Source project that contains many of the key algorithms for TLS data, designed for filtering, registration, estimation of function, surface reconstruction, modeling and segmentation, as well as structures for identifying and matching objects. The article discusses the structure of the project as well as its most useful modules from the point of view of the TLS data processing. It describes the format used by the PCL data storage. Also, a practical example is enclosed, as a basis for the discussion of consecutive steps of working with the library, from recording input data in the correct format to visualization of the effects of the used algorithm.