Local variables

Local variables start with a lowercase letter and are declared when they are first assigned a value. A variable name can start with an underscore _, but as these names are reserved for the compiler, it is not recommended to start a variable name with an underscore.

animal = "Cat"
age = 3

The variable type depends on its usage and not only from their initializer, thus it doesn’t need to have a type specified. Usually, a variable is a value holder associated with the type it is expected to have according to its location and usage within the program. So if a variable is reassigned with a different expression it will inherit that expression’s type instead. animal = "Cat" #=> animal is a String type animal = 4 #=> animal is an Int32 type