What are the advantages and features of different types of collections in Kotlin do you know?

In Kotlin, there are several core collection types, divided into mutable (Mutable) and immutable (Read-only).

• List — an ordered collection of elements. In the immutable version (List), you cannot modify the contents, while in the mutable (MutableList), you can add, remove, and change elements.
• Set — a collection of unique elements. Set is immutable, MutableSet is mutable.
• Map — a collection of key-value pairs. Map is immutable, MutableMap is mutable.

Features:

• Immutable collections are safe for multithreaded access without synchronization.
• Mutable collections allow dynamic modification of contents.
• Kotlin provides convenient extension functions for working with collections (filtering, transforming, aggregating).

Example:

val readOnlyList: List<Int> = listOf(1, 2, 3)
val mutableList: MutableList<Int> = mutableListOf(1, 2, 3)
mutableList.add(4) // now the list contains 1, 2, 3, 4

val readOnlySet: Set<String> = setOf("a", "b")
val mutableSet: MutableSet<String> = mutableSetOf("a", "b")
mutableSet.add("c")

val readOnlyMap: Map<String, Int> = mapOf("one" to 1, "two" to 2)
val mutableMap: MutableMap<String, Int> = mutableMapOf("one" to 1)
mutableMap["two"] = 2