Much research is being done on alternative antibacterial therapies that replace or supplement conventional antibiotics since multidrug-resistant bacterial infections are becoming more prevalent. Metallic nanoparticles have been demonstrated to destroy bacterial biofilms successfully. However, their chemical manufacture frequently results in harmful byproducts. Recent research has shown that the environmentally friendly production of metallic NPs may be accomplished using microbial and plant extracts. The NPs can effectively limit bacterial growth by passing through the exopolysaccharides of a biofilm matrix. A cluster of sessile microbial cells forms a biofilm group that may cling to surface biological and nonliving things, through glycocalyx and additional polymeric molecules. Such biofilms result in biofouling on implants and medical equipment and several chronic disorders. NPs that penetrate the biofilm change the QS gene pathways, impairing cell-to-cell communication and preventing the formation of the biofilm. Algae, which create a variety of biogenic chemicals, have been discovered to be capable of destroying biofilms without negatively affecting the ecosystem and other biotas. The main component of the algal extract with antibacterial and anti-biofilm properties is polyunsaturated fatty acids. The extracts from roughly 225 different species of cyanobacteria and microalgae exhibit anti-biofilm action. This section is focused on the “signal jamming effects” of different metallic and nonmetallic nanoparticles produced by microbial nanotechnologies on biofilms’ development.