The use of thoracic ultrasound as a diagnostic tool in the emergency department, intensive care unit or in patients with pulmonary diseases is increasing steadily. It is used to guide percutaneous tracheostomies, to assess pleural effusions, to rule out pneumothorax, and to guide the placement of endovascular and pleural catheters. It is also useful in the assessment of patients with dyspnea. The aim of this review is to provide the practical and technical basics for the use of this diagnostic tool among internists and specialists in pulmonary diseases.