Update README.md

README.md

@@ -1 +1,25 @@
 # `jam`
+
+`jam` is a command-line tool for buildpack authors and users. The `jam` name is simply a play on
+the idea of "packaging" or "packing" a buildpack.
+
+`jam` comes with the following commands:
+* help                : Help about any command
+* pack                : package buildpack
+* summarize           : summarize buildpackage
+* update-builder      : update builder
+* update-buildpack    : update buildpack
+* update-dependencies : update all depdendencies in a buildpack.toml according to metadata.constraints
+
+The `jam` executable can be installed by downloading the latest version from
+the [Releases](../../releases) page. Once downloaded, buildpacks can be created from
+a source repository using the `pack` command like this:
+
+```sh
+jam pack \
+  --buildpack ./buildpack.toml \
+  --stack io.paketo.stacks.tiny \
+  --version 1.2.3 \
+  --offline \
+  --output ./buildpack.tgz
+```