What is Enumeration in Swift?

Ans : 

What is enum?

An enumeration defines a common type for a group of related values and enables you to work with those values in a type-safe way within your code.
Enumerations offer an easy way to work with sets of related constants. An enumeration, or Enum, is a symbolic name for a set of values. Enumerations are treated as data types, and you can use them to create sets of constants for use with variables and properties.

When to use an enum?
Whenever a procedure accepts a limited set of variables, consider using an enumeration. Enumerations make for clearer and more readable code, particularly when meaningful names are used.

The benefits of using enumerations include:

• Reduces errors caused by transposing or mistyping numbers. 
• Makes it easy to change values in the future. 
• Makes code easier to read, which means it is less likely that errors will creep into it. 
• Ensures forward compatibility. With enumerations, your code is less likely to fail if in the future someone changes the values corresponding to the member names.