It is written in English and uses U.S. Crochet Terms
It uses basic Crochet Stitches such as:
Single Crochet
Increase
Decrease
Half Double Crochet
Double Crochet
Slip Stitch

It uses the following colors:
Light yellow,
Brown,
White,
Red,
Black,
Green - optional

it should work with any yarn type, just make sure to use the correct hook size for the yarn type you are using.