A string is a basic data type in a programming language. In Kotlin, the String class represents character strings. Kotlin string literals are implemented as instances of this class. Kotlin uses double quotes to create string literals. Kotlin has a rich API for working with strings. It contains plenty of methods for various string operations. Kotlin/Java strings are immutable, which means that all modification operations create new string instead of modifying a string in-place.
Strings are a sequence of characters. For example, “Hello there!” is a string literal.In Kotlin, all strings are objects of String class. Meaning, string literals such as “Hello there!” are implemented as instances of this class.
Here, myString is a variable of type String. You can declare variable of type String and specify its type in one statement, and initialize the variable in another statement later in the program.
As we know, String objects are immutable. With each concatenation using the + operator or plus() method, we get a new String object. In contrast, to avoid unnecessary String object creation, we can use a StringBuilder.Hence, StringBuilder creates a single internal buffer that contains the final string.
Therefore, StringBuilder is more efficient when concatenating a large number of strings.Kotlin also has a feature called String templates. String templates contain expressions that get evaluated to build a String.String template expressions start with a dollar sign followed by variable’s name.