class Array: en. wikipedia.| docs.ruby-lang.org
class Integer: An \Integer object represents an integer value. literals.| docs.ruby-lang.org
class String: A +String+ object has an arbitrary sequence of bytes, typically representing text or binary data. new or as literals.| docs.ruby-lang.org
class Rational: b (b>0), where a is the numerator and b is the denominator. mathematically.| docs.ruby-lang.org
class Hash: A +Hash+ maps each of its unique keys to a specific value. An Array index is always an Integer.| docs.ruby-lang.org
class Float: A \Float object represents a sometimes-inexact real number using the native architecture's double-precision floating point representation. Floating po| docs.ruby-lang.org
class Complex: i>. en.| docs.ruby-lang.org