Ruby no variable declaration

code.java

public class Main {
  public static void main(String[] args) {
    int a = 1 + 1;
    int b = 2;
    while (a < 1000) {
      a += 1
    }
    c = "hello there"  // would give an error type of variable not stated
    a = "this is a string" // would also give an error types cannot change
  }
}

ruby.rb

def long_method
  a = 1 + 1
  b = 2
  while a < 1000 do
    a += 1
  end
  
  c = "hello there"
  a = "this is a string"
end