Why does the ideal gas state equation fail at high pressures for real gases?

[Bugsy23]

Why does the ideal gas state equation fail at high pressures for real gases? I think it has something to do with the forces between the molecules in the gas, but I'm not sure the exact reason

 

[Feldoh]

It has to do with the compressibility of non-ideal gases which is due to some extent to the forces between molecules.

For really high pressures it also has to do with quantum effects due to the properties of indistinguishable particles and the Pauli exclusion principle.