Logical Data Modeling - Value (Operand) in code
In a dynamic language, only the value has a type (not the variable)
Every value has a type.
Variable are a component to manage state.
Values that are included directly in the source code are called literals.
Object value are held by reference (ie the address of the value). Two objects are the same if they have the same address value.
The equality function/operator for an object may be also define to change this behavior.