Quiz 2 (for newbies only)

[Eureka_sg]

phew! The previous one was answered so fast. : )
I should have specified (for newbies only).
Experts, pls skip this node.

Seems that there are always many newbies lurking around but never had the chance to post replies; either the question was too tough or the masters were too finger-ready.
So I thought I would post some simple questions for newbies to share their knowledge with other newbies as well.

Question: 1..9 and 1-9 both means 1,2,3,4,5,6,7,8,9. So what's the difference between them?

[dailylemma]

1..9 can be used to represent 1,2,3,4,5,6,7,8,9 in a for loop, but 1-9 will be evaluated as -8 in this context.

On the other hand, 1-9 can be used in regexes for the same purpose