Historically animal studies and 2D cell culture models have been strengthening biomedical and pharmaceutical research, with many limitations. Currently, new drug development for many diseases like cancer is an important necessity. An organoid is a miniaturized version of an organ produced in vitro that shows realistic micro-anatomy, is capable of self-renewal and self-organization and exhibits similar functionality as the tissue of origin. While their size is small (typically __ampersandsignlt; 3 mm in diameter), organoids are stable model systems of organs and tissues that are amenable to long-term cultivation and manipulation. They are classified into those that are tissue-derived and those that are stem cell-derived. They help in both in vivo and in vitro investigation and represent one of the latest innovations in the research for a model to recapitulate the physiologic processes of whole organisms. They reduce experimental complexity, and are compliant to real-time imaging techniques, and more importantly, they enable the study of aspects of human development and disease, drug toxicity in a clear fashion that is not easily or correctly modelled in animals and 2D cell cultures. However 3D organoids have also had some limitations like vascularity, inflammatory system, etc. Despite these limitations, it is evident that organoids have great potential to revolutionize the way we approach disease modelling, drug discovery, and toxicology.