If...ElseIF....Else
IF
IF Condition do Visual Logic Sub-Block
Tests the condition and if this is successful obeys the lines of Visual Logic in the sub-block.
ELSE IF
ELSEIF Condition do Visual Logic Sub-Block
If and only if none of the preceding IF / ELSEIF lines in a continuous sequence at this indent level have been successful ELSEIF tests the condition and if this is successful obeys the lines of Visual Logic in the sub-block.
ELSE
ELSE do Visual Logic Sub-Block
If and only if none of the preceding IF / ELSEIF lines in a continuous sequence at this indent level have been successful obeys the lines of Visual Logic in the sub-block without testing any further conditions.
You can find a simulation example on IF/ ELSEIF here: IF.s8