Create S4 class and its new method in R?

[pizzafries]

New to R language and don't know much about S4 classes. I am trying to solve a question

Q. How would you create a new S4 class and its new method? 
Create a laptop class, then create an Apple Macbook Pro object
and define a show function to display its CPU type to demonstrate the process.

I created the class using:

setClass("Laptop", slots=list(name="character", CPU_type ="character"))
cl <- new("Laptop",name="Apple Macbook Pro", CPU_type = "8-core CPU")
cl
# Output
An object of class "Laptop"
Slot "name":
[1] "Apple Macbook Pro"
Slot "CPU_type":
[1] "8-core CPU"

Now, I have 3 concerns.

1. Is this S4 class correct?
2. I don't know how to define show function that will display the CPU type to demonstrate the process.
3. I don't understand what does this and its new method means?

Can some one help me out?

Thanks.

[williaml]

Hi, it looks fine.

For #2, I think you are after

cl@CPU_type

which returns "8-core CPU".