Declaring variables is done using the var or const keyword. With var, you declare a mutable variable, with const you declare an immutable variable.

const std = @import("std");
const print = std.debug.print;


pub fn main() void {
    const immutable_number: i32 = 5;  
    var mutable_number: u32 = 5; 
    mutable_number +=1;
    print("{d} {d}\n", .{immutable_number, mutable_number});
    
    var boolean: bool = true; 
    print("{}\n", .{boolean});
    
    const float: f32 = 3.14; 
    print("{d}\n", .{float});
    
    var msg = "string literal"; 
    print("{s}\n", .{msg});
}

Notice how the type of the last variable was inferred.

Running the program gives the following output:

$ zig run .\variables.zig
5 5001
true
3.140000104904175
string literal

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