Ruby is a powerful, flexible programming language you can use in web/Internet development, to process text, to create games, and as part of the popular Ruby on Rails web framework. Ruby is: *Hi...

In Ruby, your information (or data) can come in different types. There are three data types in Ruby that we're interested in right now: numbers, booleans (which can be true or false), a...

One of the most basic concepts in computer programming is the variable. You can think of a variable as a word or name that grasps a single value. For example, let's say you needed the number 25...

Ruby isn't limited to simple expressions of assignment like [...] ; it can also do all the math you learned about in school. There are six arithmetic operators we're going to focus on: Addition ...

The [...] command just takes whatever you give it and prints it to the screen. [...] (for "put string") is slightly different: it adds a new (blank) line after the thing you want it to print. Y...

Because everything in Ruby is an object (more on this later), everything in Ruby has certain built-in abilities called methods. You can think of methods as "skills" that certain objects have. F...

Methods are summoned using a [...] . If you have a string, [...] , and take the [...] of it, Ruby will return the length of the string (that is, the number of characters—letters, numbers, space...

The [...] method is called the same way [...] is, but instead of asking Ruby to tell you how long a string is, it spits out a backwards version of the string you gave it. For instance, [...] ...

Let's try one more method (er, two methods). As you might have guessed, the [...] and [...] methods convert a string to ALL UPPER CASE or all lower case, respectively.

You probably saw us use the [...] sign a few times in earlier exercises. The [...] sign is for comments in Ruby. A comment is a bit of text that Ruby won't try to run as code: it's just for...

You can write a comment that spans multiple lines by starting each line with a [...] , but there's an easier way. If you start with [...] and end with [...] , everything between those two exp...

There are many different kinds of variables you'll encounter as you progress through these courses, but right now we're just concerned with regular old local variables. By convention, these var...

Let's quickly review how to declare and set variables. Remember, you declare a variable just by saying its name, and you set it using [...] . You can always check the Hint below if you need mo...

Good! Now let's do a little math.

Well done! Let's do a little review of string methods. Remember, you call a method by using the [...] operator, like this: [...] .

Great work! For our last review exercise for this lesson, let's go over single- and multi-line comments.