In Rebol2/3 we had the following conditionals
- if value [ ]
- either value [true][false]
- all [val1 val2 val3 ...]
- any [val1 val2 val3 ... ]
- switch val [ val1  val2 ...] and switch/default
- case [ val1  val2  true ] and case/all
- while [condition][body]
- until [block]
With ren-c there are some new variations on these, and these can be a source of confusion.
We also have now
there's some information on the trello porting card on some of these.