What do the router lights mean?

I have a Hawking 4 port router- PN9249. I can't find a manual
online anywhere & I seem to have lost mine.

There are 2 rows of 5 lights across the front.[WAN & 4 Ports] They
appear to be labeled on the left side-- but the labels don't help me.

Top row- Link/activity
Bottom Row- 10/100

What does the 10/100 light indicate? One of mine is out & it goes
to the computer that is acting up on my LAN. [It can't even ping
anyone else though it sees one other computer and can be pinged from
yet another.]

I spent a few days trying to get the reprobate working before I
noticed the router light. Changing the cable to another link moves
the 'off' light to that link.

Hopefully knowing what it means will help me diagnose the problem.
[2of the computers on my LAN are W98SE & it is one of them that I'm
having trouble with. Comparing the ipconfig results between the 2 -
the only thing different is the NIC & its physical address.]

Thanks,
Jim