Both IMRT and SBRT are image guided - it's not a separate type. (That wasn't always the case with IMRT, but it is most often nowadays. And technically, SBRT is
intensity modulated (IMRT), but we usually mean conventionally fractionated when we say IMRT). External beam also includes proton and carbon ion (in Japan, Germany, China & Italy). IMRT and PBRT may also be hypofractionated.Then there are combinations - IMRT with an LDR brachy boost, IMRT with a proton boost, SBRT with a brachy boost, etc.
Of course, nuclear medicine (e.g., Xofigo, Lu-177-PSMA) is also a kind of radiation.
And if you want something really out of the box,there's this:/pcnrv.blogspot.com/2016/08/intra-operative-electronic.html