UK knitting Books vs. USA Knitting Books

I have just purchased a few vintage knitting books from Australia and the UK. Is there a difference in Yarn or the Plys?
The patterns are for Baby Doll clothes. Dresses, hats, etc.
The pattern calls for [I][COLOR=#800080]Knit in 8 ply (double knitting) (worsted weight) yarn [/COLOR][/I]
Will this yarn be the same for the US as for the UK?
Is yarn universal? :think:

The yarn is basically the same but in UK patterns the required yarn is usually measured in weights rather than length. We usually have double knit, Aran chunky or 2,3 or 4 ply. I had never heard terms such as worsted, fingering or sport until I started reading American patterns, but I found conversion charts online such as helpful to work out substitutes

Also some knitting terms and abbreviations are different such as Cast-off is the same as bind-off in America.

Thank you for your help.
I will def. use this chart.

I also found a vogue knitting guide to terms that had UK equivalents and a rather more amusing if brief UK/US knitting translator.