Key Concepts

Review core concepts you need to learn to master this subject

Ruby Hash

Ruby Array

Ruby Hash New

Ruby Hash Bracket Notation Adding Pairs

Ruby Multidimensional Arrays

Ruby Array Index

Ruby Method .Each

Ruby Hash Bracket Notation Value

Ruby Hash

profile = {
  "name" => "Magnus",
  "profession" => "chess player"
  "ranking" => 1,
  "grandmaster?" => true
}

# "name", "profession", "ranking", and "grandmaster?" are the keys. "Magnus", "chess player", 1 and true are the values.

puts profile["name"] # => Magnus

In Ruby, a hash is a collection of key-value pairs.

A hash is denoted by a set of curly braces ({}) which contains key-value pairs separated by commas. Each value is assigned to a key using a hash rocket (=>). Calling the hash followed by a key name within brackets grabs the value associated with that key.

Data Structures
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