Update Ground Types

Ground-Types.md

@@ -2,6 +2,6 @@ Ground has 5 built-in types, which all hold a different purpose.
 
 - int: This stores a signed 64-bit integer. As CGround is written in C, integer overflow/underflow is **undefined behaviour**.
 - double: This stores the same values as a C double, i.e. 1 bit sign, 11 bit exponent, 52 bit mantissa.
-- string:
-- char:
-- list:
+- string: This stores an immutable sequence of characters, stored in memory as a `const char*`.
+- char: This stores a single character.
+- list: This stores an array of variables.