You can create a String either by using a string literal or creating an instance of a String class
Some times we need to execute a block of code several number of times.
Swift 4 provides the following types of decision making statements.
An operator is a symbol that tells the compiler to perform specific mathematical or logical manipulations.
A literal is the source code representation of a value of an
Constants refer to fixed values that a program may not alter during its execution.
Swift 4 also introduces Tuples type, which are used to group multiple values in a single compound Value.