restructuring to separate language from API

docs/blocks/variables/assign.md

@@ -0,0 +1,36 @@
+# Assignment Operator
+
+Use an equals sign to make a [variable](/blocks/variables/var) store the [number](/reference/types/number) 
+or [string](/reference/types/string) you say.
+
+When you use the equals sign to store something in a variable, the equals sign is called
+an *assignment operator*, and what you store is called a *value*.
+
+### Storing numbers in variables
+
+This program makes the variable `item` equal `5` and then shows it on the [LED screen](/device/screen).
+
+````blocks
+let item = 5
+basic.showNumber(item)
+````
+
+### Storing strings in variables
+
+This program makes the variable `name` equal `Joe` and then shows it on the [LED screen](/device/screen).
+
+````blocks
+let name = "Joe"
+basic.showString(name);
+````
+
+### Notes
+
+You can use the assignment operator with variables of 
+every [type](/reference/types). A *type* is which kind of thing
+a variable can store, like a number or string.
+
+### See also
+
+[variable](/blocks/variables/var), [types](/reference/types)
+