Silver nanoparticles are small-sized particles of silver that are in the range of 1 and 100 nm in size. Silver nanoparticles pose unique features which help in diagnosis, treatment, drug delivery, as well as in medical devices that are used in several biomedical but environmental applications also. The review presents that the most important methods used for silver nanoparticle synthesis are the physical and chemical methods. The problem with using the physical and chemical methods is that the synthesis is expensive, involves a high amount of energy, and can generate toxic substances. To remedy these aspects, the biological synthesis method presented a reasonable alternative. Even though silver nanoparticles are intensively used in many important applications, such as biomedical and environmental fields also, they still have their downsides when it comes to toxicity. This review provides a comprehensive point of view on the synthesis routes, various important applications, and also the health and environmental issues that are caused by these nanoparticles. The focus of the review is pointed on the effective and efficient synthesis of silver nanoparticles while exploring/ considering their various prospective applications besides trying to understand the current context on the toxicity problems which concern these nanoparticles.