+Variables can retrieved simply by referring to them by name. For
+example, to add `8` to the variable `foo` and store the result in
+`bar`, you would do the following:
+
+[[!sweavealike echo=1 results="hide" code="""
+bar <- foo + 8
+"""]]
+
+
+In R, variables are more correctly called objects, because they have
+structure and do not directly refer to a specific memory location.
+
+Basic Types
+----------
+
+Vectors
+=======
+
+A vector is the major data type used in R. You can think of it as a
+line of cells, each containing a value of the same type.
+[Type here means a number or a string.]
+
+
+Lists
+=====
+
+
+Object Attributes
+-----------------
+
+
+