in go there is arrays, with fixed size: [32]byte - often found for hash functions, and much more common are dynamic arrays or "slices" which are []byte
byte is a synonym for uint8 or unsigned 8 bit integer and they are used constantly for all types of things except for the last leg often if it's text it comes out as string, the two can be interchanged in many cases but strings are immutable, the only immutable objects in Go aside from constants - they are the only structured type that can be a constant in go