Julia is a strongly typed language allowing the programmer to specify a variable's type precisely. However in common with most interpreted languages it does not require the type to be declared when a variable is declared, rather it infers it from the form of the declaration.

A variable in Julia is any combination of upper or lowercase letters, digits and the underscore (_) and exclamation (!) characters. It must start with a letter or an underscore _. Conventionally variable names consist of lowercase letters with long names separated by underscores rather than using camel case.

To determine a variable type we can use the typeof() function.

So typically:

julia>  x = 2;   typeof(x)  #  =>  gives Int64
julia>  x = 2.0;  typeof(x) # =>  gives Float64

Notice that the type (see the preceding code) starts with a capital letter and ends with a number which indicates the number of bit length of the variable. The bit length defaults to the word length of...