Life on the planet is conditioned by water. Water is not just a physicochemical entity; it is a phenomenon in itself. When water deviates from playing its original role and becomes hazardous for health and/or unfit for other intended uses due to the introduction of some undesirable substances (inorganic, organic, radiological, and biological), or a factor (such as heat raising its temperature), is what water pollution is. The water pollution sources can typically be classified into natural and anthropogenic sources. Anthropogenic sources are of two types: point sources and nonpoint sources. Apart from these, some new sources are also being encountered in our contemporary world. Water bodies often get polluted by natural means, such as leaching of minerals and many toxic metals from rocks, siltation of rivers, decomposition of dead plants and animals, natural erosion processes like weathering, increased rates of glacier melt in summer, volcanic eruptions, and wildfires. When water pollution originates from a single identifiable source, it is called point source pollution. Industries, sewage, and agricultural practices using chemical fertilizers and pesticides are the top point sources of water pollution. Nonpoint sources contribute to pollution through indirect pathways, atmospheric deposition, and runoff. Some new emerging sources of water pollution include microplastics, pharmaceutical and personal care products (PPCPs) and their ingredients, like shampoos, detergents, soaps, lotions, dyes, creams, etc., and hot wastewaters increasing temperatures of a water body leading to ecological consequences.