After learning that there are several ways to start fluorescent tubes on magnetic ballasts without starters, which include rapid start, trigger start, quickstart, semi resonant start, and perfekt start; I wonder what is the difference between each term and i would be interested in knowing the definition of each term and whether some of the terms refer to the same starting circuits.

'rapid start' & 'trigger start' are the same thing, just different filament heating voltages.

'perfekt start' *from my understanding* is simply a standard preheat choke/ballast but with a thermal starter I believe the name is a registered trademark of a lighting company in Israel?

'semi resonant start' or SRS I know does operate somewhat like rapid start in that the filaments are heated...but I think it forms some sorta resonant feedback loop? (can't remember how I saw it explained) one of the UK guys can certainly give true details on its operation.
(in *appearance* the startup looks like a RS (I have a couple SRS ballasts) but its actual operation is different)

'quickstart', I don't know but I once saw it said that basically same thing as rapid start, just UK name for it.

Most of the terms mean the same as the others, just used in other parts of the world.
The "semiresonant" means it may at first glance look like resonant, but it is not working in resonance at all. It is in fact what in the US is called rapid start, just the filaments are heated by a high impedance current source (via the capacitor connected in series with the filaments), instead of a low impedance voltage source (low voltage auxiliary secondary winding in the transformer assembly).

E.g. "programmed start" is the term used practically only in the North America, Europe uses the "warm start" for the same functionality in the resonant stsrt HF ballasts.

And some terms ("Perfect start", "Quickstart",...) are just proprietsry marketing BS terms  (some are even registered trade marks).

All of them are "designed" and mainly used as marketing term, so you can not take them to the letter and expect to mean something exact. They may indicate certain principles, but only to some extend, they definitely do not mean anything exact.

Perfektstart was a trade mark from a Swiss ballast maker called Knobel AG Ennenda which then later became Tridonic.

Knobel patented a very reliable thermal starter which was integrated in a fluorescent lamp ballast.