New to mac, g3 ibook-which os do I need?

I just received a 12.1" g3 ibook but there is not an operating system installed and I'm not sure what I need. I've had people tell me to just get linux and it would work, but I would rather have a mac os. Does anyone know which os is compatible with these specs?

Hard Drive Capacity: 10 GB
Processor Type: PowerPC G3
Processor Speed: 500 MHz
Memory (RAM): 128 MB

Any help I really would appreciate, I've been trying to do the research on my own for the past week now and have pretty much gotten no where.
Thank you!

10.4 would be able to run on it. But as far as I've tested Os X 10.3 runs best and most speedily on the G3 processor.

You can find 10.3 disks full install pretty inexspensively on Ebay.

Make sure you buy a full version or one that is specifically for the Ibook G3. Systems disks for other devices such as an imac or powermac will not work on your machine.

Okay, what about the memory though? Do I have enough space for 10.3 os x?

128MB is enough for 10.3 to run (well, enough for it to crawl lazily along.)256MB is the minimum for 10.4. I would strongly recommend getting more memory...up to the maximum of 640MB if possible.

You need 1.5GB of free space to install 10.3, and twice that for 10.4.
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