Understanding the concept of dark matter

Dark matter was initially proposed by Fitz Vicky in the 1930s after observing galaxies, but it faced skepticism until the 1980s when evidence started to accumulate. The Lambda CDM model, combining cosmology constant and cold dark matter, became the standard cosmological model by the early 2000s. Various pieces of evidence, like the gravitational effect observed when galaxies passed through each other, supported the existence of dark matter.