In the era of digital technologies many field- geologists still find it difficult to dismiss the analogical instrumentation they usually employ in their outdoor activities. They are still bound to paper maps and coloured pencils for collecting and recording data. This book is devoted to those geologists looking for an help to make a step in the digital era and take advance of all benefits of new technologies. The book is written as a technical manual and covers with an high level of detail the whole workflow from data schematization to result dissemination. The steps involved cover the analysis of to-be-collected information, the choice of most suitable hardware, the adoption and customization of software, the on-field best practices, the office data reworking, the 2D geological map dissemination and, as the final glimpse, the data transfer to 3D modelling environments. Most of the suggested software is either open source or freeware. Commercial software is used just where no adequate free tool is available for the specific purpose.