Micro-light-emitting diodes (μLEDs) are getting much attention in display industry because of their outstanding optical and electrical characteristics. μLEDs have several advantages over liquid crystal displays (LCDs) and organic light-emitting diodes (OLEDs). μLEDs are showing long lifetimes, high reliability, high power efficiencies, high brightness, and fast response times with tiny pixels. However, for commercial usage, the high production cost and low external quantum efficiency (EQE) are the major hurdles. In this review, we briefly discuss the breakthroughs in μLED technology, fabrication methods, optical/electrical characteristics, and challenges for display applications. In addition, the development of monolithic μLEDs and general device characteristics combined with various quantum dot patterning processes are systematically discussed. Potential solutions to address these challenges are also presented case by case.