A relativistic electron can emit photons in various ways :
- 1) being in nonuniform motion: synchrotron radiation, bremsstrahlung, channeling radiation, etc.
- 2) crossing and polarizing a material object: Cherenkov effect, transition radiation, parametric X-rays etc.
- 3) passing close to a material object: diffraction radiation, Smith-Purcell effect, etc.
No less than 12 ways can be listed. After writing a common basic formula, I will present the properties and applications of some of them. When possible I will use phenomenological concepts like the Equivalent Photon one. Finally I will speak of the less known phenomena of shadowing (or half-bare electron), photon impact parameter and "side-slipping" of the electron.