Strings in C#

 String is an object of System.String class that represents sequence of characters

• In C# 'string' is a keyword which is an alias for system.String class
• The literal string becomes a template when it's prefixed by the $ character, the thing is called string interpolation
  
• e.g.
  string message = $"{greeting} {firstName}! Good Morning";

String methods (System.String)

• Clone
• CompareTo : Returns integer 
• Contains
• EndsWith
• Equals : Returns boolean
• ToUpper
• ToLower
• Insert
• IndexOf
• Concat : It's a static method

StringBuilder example:

*StringBuilder class have differnet methods then System.String class e.g. Append etc.