fix typo, style
Signed-off-by: Satoshi Tanda <tanda.sat@gmail.com>
diff --git a/HACK.TXT b/HACK.TXT
index 9246179..6ef9844 100644
--- a/HACK.TXT
+++ b/HACK.TXT
@@ -35,7 +35,7 @@
$ sudo ./make.sh install
At the same time, for Java/Ocaml/Python bindings, be sure to always use
-the bindings coming with the core to avoid potential incompatility issue
+the bindings coming with the core to avoid potential incompatibility issue
with older versions.
See bindings/<language>/README for detail instructions on how to compile &
install the bindings.