Triboemission comprises the emission of low energy electrons and photons, the eventual formation of micro-triboplasmas, and the possible charge-initiated tribochemical reactions on the surfaces under contact. Electron triboemission is often seen as a case of electron exoemission, but such low-energy output may be just a fraction of the total electronic excitation on the surface, the majority of which may proceed as internal currents. The dynamics of these related surface phenomena have been investigated by different techniques, which are discussed in this work; in particular, the authors have obtained extensive data indicating that electrons and photons are produced from mechanical surface work, particularly from surface oxides and semiconductors under contact sliding in vacuum. This paper also discusses the existing body of work on triboemission, and the possible use of the developed measurement techniques as novel probes for surface processes.