Family 1

Family 2

Family 3

Particle

Mass

Particle

Mass

Particle

Mass

Electron

.00054

Muon

.11

Tau

1.9

Electron-neutrino

< 10-8

Muon-neutrino

< .0003

Tau-neutrino

< .033

Up-quark

.0047

Charm Quark

1.6

Top Quark

189

Down-quark

.0074

Strange Quark

.16

Bottom Quark

5.2

Table 1.1 The three families of fundamental particles and their masses (in multiples of the proton mass). The values of the neutrino masses have so far eluded experimental determination.