This is an introduction to programming.  The material is geared towards
beginners w/little to no experience.  Material is being added and created as a
group of teens are learning to program in Ruby.

Here is a walk-thru of program 1

class/2/io_and_ifelse.rb


Let's start by asking for a name (using puts, short for put string), getting
the name (using gets, short for get string)  and printing that name.

commit d8dcf071d06b642fe85bcad36d61ff6a09014e74

Let's use the method print instead of puts for the question because puts adds a newline

commit 4d6317fd05bfb892db3e37eeabb2b89a8e53d8de

That looks better, but let's also use the chomp method to get rid of the
newline that the gets method grabs

commit 2722175121ce5429f9835eba0b273622f6683b00

Let's add some comments for our code.  Comments allow us to write notes for
ourselves and other humans to read.  The computer ignores them


commit 7d219dfe3aad4410c603be765cabcd124a484ee6

Notice the special syntax inside of the string that allows us to use the
variable.  You can also do other things in with in those braces.  For instance
reverse the string using the reverse method


commit 00880253e5f85a3d81fca9bb0b41396bba33adf5

Let's ask for age in addition to name.  Ruby allows us to chain methods
together by passing the results of one to the next.  Since gets returns a
string we can pass it directly to chomp to remove the newline

commit 8c5e692168188d3ce794750d8962ce56ede7539c

By using an if conditional statement we can decide to do something or not based
on the outcome of the condition.  Let's check the age before printing


commit 0d54b06b7043e4c9acaeac9d73084c31d2ce2943

Oops. The variable age is a string because gets returns a string.  We tried to
compare a string to a number and that does not make sense so the program
complains and stops.  We can use the to_i method to change the string into a
number

commit f97f05fb964cd8fdbb3dcabe3d890604d9e03045

Besides if there are other conditionals like elsif (short for else if) which
tries another condition as well as else, which is a fall back if nothing else
matches.  You can also test multiple conditions by using "and" and "or".

commit 24112ec9b2067f60d9514c9b00921b12425d48a0