This paper describes various methods of synthesising colloidal silver. Particular emphasis is placed on green synthesis using various natural reducing agents. Green synthesis refers to methods of chemical synthesis that use environmentally friendly processes and materials. The aim is to reduce or eliminate the use and production of hazardous substances and to replace non-renewable sources with renewable materials. Green synthesis is used in a variety of areas, including the production of medicines, materials and nanotechnology. Silver nanoparticles have a wide range of applications due to their unique properties. Some of the applications are: Medicine, water purification, textile industry, electronics, catalysis, etc. Due to the wide application of silver nanoparticles, the impact on the environment is a concern from year to year as the synthesis uses various raw materials and chemicals that are expensive, toxic and hazardous to the environment. In recent years, green synthesis has therefore become increasingly popular because it is more environmentally friendly and profitable, i.e. lower production costs, lower energy consumption and reduced or complete elimination of toxic chemicals. Toxic chemicals have been replaced by natural substances from the environment that are readily available, such as plant extracts and microorganisms.