Update index.md (#22824)

Edited for clarity, added clarification on the assignment operators and gave examples of types of objects.

guide/english/r/objects/index.md

@@ -3,25 +3,42 @@ title: Objects in R
 ---
 ## Objects
 
-R allows to save the data by storing it inside an R object. 
+R allows the user to save the data by storing it inside an object. 
 
 ## What’s an object?
 
-It is just a name that you can use to call up stored data. For example, you can save data into an object like a or b.
+An object is a name that you can use to call up stored data. For example, you can save data into an object like a or b.
 ```r
 > a <- 5
 > a
 [1] 5
 ```
 
+There are many types of objects in R. Two of the most common are as lists and functions.
+Example of a list:
+```
+> a <- list(1, "Hello, world!", FALSE)
+```
+Lists can contain mixed types of data (number, string and boolean in this example).
+
+There are many built in functions in R. The user can also make a 'user defined' function, as you see below.
+The following creates the function circleArea that calculates the area of a circle (A = π r2).
+
+```
+>circleArea <- function(r){
+  A <- pi * r^2
+  return(A)
+ }
+ ```
+
 ## How to create an Object in R?
 
 1. To create an R object, choose a name and then use the less-than symbol, `<`,
 followed by a minus sign,  `-`, to save data into it. This combination looks like an
 arrow, `<-`. R will make an object, give it your name, and store in it whatever
-follows the arrow.
+follows the arrow. You can also use the '=' sign, but this is a less common method to assign a value to an object and generally frowned upon.
 
-2. When you ask R what’s in a, it tells you on the next line. For example:
+2. When the user calls the object in the console it provides the output on the next line. For example:
 
 ```r
 > die <- 1:6
@@ -38,7 +55,6 @@ Second, a name cannot use some special symbols, like  `^,  !,  $,  @,  +,  -,  /
 5. You can see which object names you have already used with the function `ls()`.
 
 ## References
-
+ - [Official Docs](https://cran.r-project.org/manuals.html)
- * [Official Docs](https://cran.r-project.org/manuals.html)
+ - [Objects in R by r-bloggers](https://www.r-bloggers.com/classes-and-objects-in-r/)
- * [Objects in R by r-bloggers](https://www.r-bloggers.com/classes-and-objects-in-r/)
+ - [CRAN](https://cran.r-project.org/doc/manuals/r-release/R-lang.html)
- * [CRAN](https://cran.r-project.org/doc/manuals/r-release/R-lang.html)