Q: my apple computer is a 10.5.8 osx with 2GB memory can I upgrade this computer?

It depends on what model of Mac you have. If it's a PowerPC-based Mac, 10.5.8 is the last version your system can run. If you have an Intel-based Mac, you can probably upgrade at least to Mac OS X 10.6 Snow Leopard:

http://support.apple.com/kb/SP575

but whether you can upgrade further will again depend on the specific model you have. If you'll tell us, we can tell you the versions of OS X it can run.

Regards.

Choose About this Mac from the Apple menu, click the version twice, append the last three characters of its serial number to http://www.everymac.com/ultimate-mac-lookup/?search_keywords= , and load the page. This will tell you what its maximum Mac OS X version is.

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