diff --git a/README.md b/README.md
index 43340ef..3f4aa8f 100644
--- a/README.md
+++ b/README.md
@@ -3,4 +3,17 @@ Dockerfiles for building with g++/gcc on Ubuntu with valgrind and gdb
 Getting Valgrind to work is a pain on non-Linux systems like Windows and MacOS. dliu/ubuntu-gcc-valgrind is an image that combines Valgrind with the normal build chains for C/C++ including gdb, gcc, g++, etc.
 
 
+Usage: 
+
+Open a terminal into your container to use gcc/valgrind, you can do:
+
+	docker run --rm -it -v `pwd`:/app dliu/ubuntu-gcc-valgrind /bin/bash
+	root@xxxx# <enter commands here>
+
+You can also directly invoke commands (gcc, valgrind, etc) like this:
+
+	docker run --rm -it -v `pwd`:/app dliu/ubuntu-gcc-valgrind gcc -c hello.c
+	docker run --rm -it -v `pwd`:/app dliu/ubuntu-gcc-valgrind valgrind ./a.out
+
+
 
diff --git a/build.sh b/build.sh
index 67a058f..b309b8b 100755
--- a/build.sh
+++ b/build.sh
@@ -1,3 +1,3 @@
 # To build the image from Dockerfile, use this command:
-#docker build -t="dliu/valgrind" .
+#docker build -t="dliu/ubuntu-gcc-valgrind" .
 
diff --git a/run.sh b/run.sh
index 7b1aff6..8f5e465 100755
--- a/run.sh
+++ b/run.sh
@@ -1,4 +1,4 @@
 # The workdir is set to be /app. Run your image mounting your 
 # application directory to /app like below:
-docker run --rm -it -v `pwd`:/app dliu/valgrind /bin/bash
+docker run --rm -it -v `pwd`:/app dliu/ubuntu-gcc-valgrind /bin/bash