Master the foundation of modern Scala development by exploring five essential functional programming abstractions. This guide takes a deep dive into algebraic structures, starting with Semigroup and Monoid for combining values. It progresses to type constructors, explaining how Functors transform wrapped data, Applicatives combine independent contexts, and Monads sequence dependent computations. By understanding these core patterns, developers can write more polymorphic, composable, and algebraically sound Scala code that works across diverse data types.

Scala collections are a powerful feature providing rich data structures for working with sequences, sets, and maps. The collection hierarchy comprises three main types: Sequence for ordered indexed access, Set for unique elements, and Map for key-value pairs. Scala emphasises immutable collections by default, ensuring thread-safety and referential transparency, while mutable collections enable efficient in-place modifications. Key collection types include List for linked list operations, Vector for random access, and Range for memory-efficient numeric sequences. Understanding the distinction between immutable and mutable collections is essential for writing safe, concurrent Scala code. Iterators enable lazy evaluation, allowing efficient processing of large datasets without consuming memory.