Update readme

Author: peter-evans

README.md

@@ -6,11 +6,15 @@
 
 Go implementation of the Patience Diff algorithm.
 
+## About
+
+Patience Diff is an algorithm credited to [Bram Cohen](https://bramcohen.livejournal.com/73318.html) that produces diffs tending to be more human-readable than the common diff algorithm.
+
 The common diff algorithm is based on the [longest common subsequence](https://en.wikipedia.org/wiki/Longest_common_subsequence_problem) problem.
 It is credited to [Eugene Myers](http://www.xmailserver.org/diff2.pdf) and is the default diff algorithm in Git.
 While the diffs generated by this algorithm are efficient, in many cases they tend not to correspond to what humans would naturally identify.
 
-Patience Diff also relies on computing the longest common subsequence, but the approach taken produces diffs that tend to be more human-readable.
+Patience Diff, while also relying on computing the longest common subsequence, takes a different approach. It only computes the longest common subsequence of the *unique*, *common* elements of both texts. This means that lines that are frequently non-unique, such as those containing a single brace or new line character, are ignored. The result is that distinctive lines, such as function declarations, become the anchor points of commonality between the two texts.
 
 ## Example
 
@@ -114,7 +118,5 @@ diff := patience.DiffText(diffs)
 
 ## References
 
-The patience diff algorithm is credited to Bram Cohen. 
-
 - [Patience Diff Advantages](https://bramcohen.livejournal.com/73318.html) by Bram Cohen
 - [Patience Diff, a brief summary](https://alfedenzo.livejournal.com/170301.html) by Alfedenzo