The Chandrasekhar limit is the value at which the mass of bodies composed by electron-degenerated matter is restricted. These bodies consist of nuclei, which are immersed in a gas of electrons. The limit is about 1.4 solar masses. This is the reason why white dwarfs, which are made up of electron-degenerate matter are unable to exist in a stable configuration if its mass exceeds the Chandrasekhar limit. This is analogous to the Neutron Stars’ Tolman-Oppenheimer-Volkoff limit. This is was formulated, discovered and named after an Indian astrophysicist Subrahmanyan Chandrasekhar.
The energy of stars is produced through nuclear fusion. This heat prevents the star from collapsing. Over time, stars build up a central core, which is made up of elements that makes the temperature at the center of the star insufficient to fuse. The mass of the core of main-sequence stars are approximately below the Chandrasekhar limit. Eventually, they will lose mass as planetary nebula until they become white dwarfs, which are the remaining cores. Stars that have higher masses develop a degenerate core, which will grow until it is over the limit. This is the cause of the explosion of stars called core-collapse supernova. This will leave either a black-hole or a neutron star.