Kotlin introduces null safety features to address one of the common sources of errors in programming: null pointer exceptions. It enforces null safety at compile-time, reducing the likelihood of encountering null-related errors during runtime. Here's how Kotlin handles null safety :

1. Nullable Types : In Kotlin, the type system differentiates between nullable and non-nullable types. By default, variables in Kotlin are non-nullable, meaning they cannot hold a null value. However, nullable types can be explicitly declared by appending a question mark (`?`) to the type declaration. Nullable types allow variables to hold either a non-null value or a null value.

2. Safe Calls (`?.`) : The safe call operator (`?.`) is used to safely access properties or call methods on nullable objects. If an object reference is null, the safe call operator returns null instead of throwing a null pointer exception. It provides a concise and safe way to handle nullable objects.

3. Elvis Operator (`?:`) : The Elvis operator (`?:`) is used to provide a default value when a nullable expression evaluates to null. It allows developers to specify an alternative value to use if a nullable expression is null. 4. Non-Null Assertion (`!!`) : The non-null assertion operator (`!!`) is used to assert that an expression is non-null. It converts a nullable type to a non-nullable type explicitly. If the expression evaluates to null, a `NullPointerException` will be thrown. It should be used with caution and only when the developer is certain that the value is not null.

5. Type System and Smart Casts : Kotlin's type system performs smart casts based on nullability checks. When the compiler can determine that a nullable variable is not null at a certain point in the code, it automatically casts it to a non-nullable type. This eliminates the need for explicit type casting and allows for safer handling of nullable types.

6. Nullability in Function Signatures : Kotlin's type system incorporates nullability information in function signatures. It allows developers to specify whether a function parameter or return type is nullable or non-nullable. This provides clarity and helps ensure proper handling of nullable values in function calls.

7. Null Safety and Java Interoperability : Kotlin provides seamless interoperability with Java, which has no built-in null safety features. Kotlin treats Java types as platform types, indicating that their nullability is unknown. This ensures that null safety checks are enforced when calling Java code from Kotlin and vice versa.