paricles apart from nuetron proton and electron in an atom can be broadly divided into mesons ,leptons ,baryons .

here nuetrino is a member of lepton group(having less mass particles) which has no chrage or mass .

for any particle tere is an antiparticle so for a nurtrino its antinuetrino 

both nuetrino and anti nuetrino are difficult to dtect.