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+# What is Java?
+
+Java is a concurrent, class-based, object-oriented language specifically
+designed to have as few implementation dependencies as possible. It is intended
+to allow application developers to "write once, run anywhere", meaning that code
+that runs on one platform does not need to be recompiled to run on another.
+
+Java is a registered trademark of Oracle and/or its affiliates.
+
+> [wikipedia.org/wiki/Java_(programming_language)](http://en.wikipedia.org/wiki/Java_(programming_language))
+
+# How to use this image
+
+## Start a Java instance in your app
+
+The most straightforward way to use this image is to use a Java container as
+both the build and runtime environment. In your `Dockerfile`, writing something
+along the lines of the following will compile and run your project:
+
+    FROM java:7
+    COPY . /usr/src/myapp
+    WORKDIR /usr/src/myapp
+    RUN javac Main.java
+    CMD ["java", "Main"]
+
+You can then run and build the Docker image:
+
+    docker build -t my-java-app .
+    docker run -it --rm --name my-running-app my-java-app
+
+## Compile your app inside the Docker container
+
+There may be occasions where it is not appropriate to run your app inside a
+container. To compile, but not run your app inside the Docker instance, you can
+write something like:
+
+    docker run --rm -v "$(pwd)":/usr/src/myapp -w /usr/src/myapp java:7 javac Main.java
+
+This will add your current directory as a volume to the container, set the
+working directory to the volume, and run the command `javac Main.java` which
+will tell Java to compile the code in `Main.java` and output the Java class file
+to `Main.class`.