Studying human biology has been challenging with conventional animal models or two-dimensional (2-D) cultured cell lines. Recent advances in stem cell biology have made it possible to culture stem cells in vitro, leading to the establishment of in vitro three-dimensional (3D) organ-like structures known as organoids. Organoids are self-organizing 3D miniature tissues, that mimic the tissue architecture and functionality of in vivo counterparts. Currently, organoids can be established for multiple tissues such as intestine, brain, kidney, prostate, pancreas, liver, bladder, heart, and retina, either from pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), or adult stem cells (AdSCs). In addition to normal organoids, patient-derived tumor organoids have been established from various human tumors such as pancreatic, colorectal, breast, liver, prostate, and bladder tumors. Also, bioengineering technologies including biomaterial and scaffold fabrication, bioprinting, and microfluidics have been recently applied to create more mature and complex organoids and miniature tissues in vitro. Incorporating recently advanced computational analyses including multi-omics profiling and bioinformatics, further facilitated the process of using human organoids as a novel platform for human disease modeling, drug screening to identify potential targets and novel therapeutics, and the development of precision medicine and regenerative therapies.