documented some code

README.md

@@ -18,7 +18,7 @@ This repository is a self-contained gap buffer implementation in C which support
 * [Testing](#testing)
 
 ## What is a gap buffer?
-A gap buffer is a data structure that stores strings of text in a way that's optimized for operation based on a cursor, which makes it useful for text editors. The way it works is by dividing the memory is three regions: the text preceding the cursor, the unused memory and then the text following the cursor. The unused memory region is often referred to as "gap", hence the name "gap buffer".
+A gap buffer is a data structure that stores strings of text in a way that's optimized for operations based on a cursor, which makes it useful for text editors. The way it works is by dividing the memory is three regions: the text preceding the cursor, the unused memory and then the text following the cursor. The unused memory region is often referred to as "gap", hence the name "gap buffer".
 
 ### Insertion
 Imagine storing the string "Hello, world!" in a buffer with a capacity of 20 bytes and placing the cursor just before the "w" of "world". What the gap buffer would look like is this:
@@ -34,8 +34,6 @@ Hello, |world!
 ```
 In the diagram the cursor position was emphasized, but it's just a way to refer to the first unused byte, so it's actually redundant to specify it. 
 
-The region in the middle is usually referred as "gap" (hence the gap buffer).
-
 When text is inserted in the buffer, it's placed before the cursor and the free space is decreased. Imagine inserting the string "my " in the previous example:
 
 ```