Classes & Objects

- Classes and Inheritance
- Properties and Fields
- Interfaces
- Visibility Modifiers
- Extensions
- Data Classes
- Sealed Classes

- Generics
- Nested Classes
- Enum Classes
- Objects
- Type Aliases
- Inline Classes
- Delegation
- Delegated Properties 

Collections

- Collections Overview
- Constructing Collections
- Iterators
- Ranges and Progressions
- Sequences

- Operations Overview
- Transformations
- Filtering
- Plus and Minus Operators
- Grouping
- Retrieving Collection Parts
- Retrieving Single Elements

- Ordering
- Aggregate Operations
- Collection Write Operations
- List Specific Operations
- Set Specific Operations
- Map Specific Operations 

Other

- Destructuring Declarations
- Type Checks and Casts
- This expressions
- Equality

- Operator overloading
- Null Safety
- Exceptions
- Annotations

- Reflection
- Scope Functions
- Type-Safe Builders
- Experimental API Markers 

Native

- Concurrency
- Couroutines