What does Eddington Limit (Eddington Luminosity) Show? We know Eddington Limit (Eddington Luminosity) is calculated with this formula:

$$L_{Ed} \approx 3 * 10^4 * L_{sun} * \frac{M}{M_{sun}}$$

Example: For a black hole with $10^4 M_{sun}$, we get
$$L_{Ed} = 1.16 * 10^{35} W$$

My question is what does it really show? What do we get by calculating this Number? Is this formula really used to calculate the luminosity or it is used for calculating mass?
The Eddington limit represents the maximum luminosity that can be achieved by a body (such as the star) when there is hydrostatic equilibrium (http://astronomy.swin.edu.au/cosmos/H/Hydrostatic+Equilibrium). For luminosity greater than Eddington limit, the radiative force of the luminosity on matter exceeds the gravitational force on the matter. If the luminosity radiated by an accretion disk exceeds the Eddington limit, the matter falling towards the supermassive black hole can be blown away.