While both probiotics and prebiotics have been widely studied and used, increased usage of prebiotics in recent times has reflected a greater understanding of their multi-faceted benefits to human health. They sound similar and some may even confuse one for the other. Read on to understand the functions of each.
Probiotics are defined by the International Scientific Association for Probiotics and Prebiotics (ISAPP) as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.  In essence, probiotic supplements contain good gut bacterial species, including Bifidobacterium and Lactobacillus species. 
On the other hand, prebiotics are defined by ISAPP as substrates that are selectively utilized by the host microorganisms conferring a health benefit.  To put it simply, prebiotics act as food for the good gut bacteria to provide health benefits.
Prebiotics such as resistant starches and various types of oligosaccharides resist digestion from our human body’s enzymes and travel to the colon largely unchanged.
Our gut microbiota in the colon and the probiotic supplements we take will then feed on and ferment the prebiotics. This fermentation process produces metabolites such as short-chain fatty acids (SCFAs) that confer health benefits such as providing a main source of energy for our colon cells and having anti-inflammatory properties. 
Watch the videos from ISAPP below to learn more.