Learning for an old version of CI.

[eluser]Unknown[/eluser]
Hi there,

I've been given a system built on an old version of CI (v1.5.4 I believe) and I thought I would put in some serious time to learn CI so that I could support it effectively, my question is to learn this framework for this purpose, is it worth learning on the latest version or has too much radically changed since then (I believe 1.5.4 was about 5 years ago now)?

I haven't looked at both versions side by side closely but I would assume over so many years and through a major release (1.x.x to 2.x.x) that much had changed, but I'd rather avoid learning an outdated framework if possible but fear I may have to to support this client. Has so much changed that I would be unfamiliar with the old version having learnt the newer one?

Any advice much appreciated.

[eluser]Aken[/eluser]
The actual structure of CI hasn't dramatically changed since then (as far as I know). Some naming conventions have changed; some features added and dropped. But overall, the MVC structure and the flow of the app is roughly the same.