The electronic unit charge is magnitude of the charge on an electron. (Or a proton)
By the quantization principle of charge, electric charges appear always as discrete lumps and never continuously.
All charges can be an integral multiple of the fundamental electronic unit charge.
The magnitude of the electronic unit charge is,
PS - Although quarks which are further elementary particles constituting neutrons and protons are discovered, and they carry fractions of this electronic charge, they have never been isolated from the nucleus and as such,