Another type of lepton, in addition to the electron, is the neutrino (ν).
The most poetic summary of the properties of the neutrino was made by
John Updike, in his poem “Cosmic Gall” 6 :
Neutrinos, they are very small.
They have no charge and have no mass
And do not interact at all.
The earth is just a silly ball
To them, through which they simply pass,
Like dustmaids down a drafty hall
Or photons through a sheet of glass.