How come most descriptions of nuclear radiation only mention alpha, beta, and gamma radiation? The penetrations and dangers of such radiation are often mentioned, but the others are ignored.
Actual decay tables never seem to mention gamma radiation (Are they an unmentioned byproduct of certain decays?)

Antielection radiation is generally unmentioned for good reason, it's rare and the least penetrating form of radiation.
Neutron radiation deserves far, far more recognition though. As far as I'm aware, it's the most dangerous form of radiation for things both living and nonliving. The penetration is just right for irradiating every organ in a person's body without most of the radiation passing straight through, and it changes the properties of atoms instead of simply breaking bonds which can wreak far more havoc on biology. Plus, it tends to come in large surprise doses, since it's produced by fissile isotopes.
Are there any forms of radiation I haven't mentioned?