Silicone oils are important tools in vitreoretinal surgery because they have the ability to displace aqueous humor from the retinal surface, maintaining the adhesion between retina and retinal pigment epithelium. To understand this capability, it is important to know the silicone oil characteristics. Herein, we report first on the main chemical-physical proprieties and then we review the clinical applications of the current silicone oil which is lighter than water with particular reference to their indications with small gauge vitrectomy. Finally, we describe the surgical techniques to inject and remove this type of silicone oil. In the summary of this paper, we explain why silicone oils are today increasingly used and why their introduction has improved the prognosis of several retinal diseases. In fact, having different types of silicone oils allows us to choose the appropriate endotamponade for every single case.