I'm totally new to the Ruby world, and I'm a bit confused with the concept of Symbols. What's the difference between Symbols and Variables? Why not just using variables?

Thanks.

Variables and symbols are different things. A variable points to different kinds of data. In Ruby, a symbol is more like a string than a variable.

In Ruby, a string is mutable, whereas a symbol is immutable. That means that only one copy of a symbol needs to be created. Thus, if you have

x = :my_str
y = :my_str


:my_str will only be created once, and x and y point to the same area of memory. On the other hand, if you have

x = "my_str"
y = "my_str"


a string containing my_str will be created twice, and x and y will point to different instances.

As a result, symbols are often used as the equivalent to enums in Ruby, as well as keys to a dictionary (hash).
