diff --git a/HACKING.rst b/HACKING.rst
index 77194a3..3fef950 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -174,7 +174,7 @@
   the script on non-zero exit codes::
 
     # This script exits on an error so that errors don't compound and you see
-    # only the first error that occured.
+    # only the first error that occurred.
     set -o errexit
 
     # Print the commands being run so that we can see the command that triggers
diff --git a/exerciserc b/exerciserc
index c26ec2c..9105fe3 100644
--- a/exerciserc
+++ b/exerciserc
@@ -21,10 +21,10 @@
 # Max time to wait for a vm to terminate
 export TERMINATE_TIMEOUT=${TERMINATE_TIMEOUT:-30}
 
-# Max time to wait for a euca-volume command to propogate
+# Max time to wait for a euca-volume command to propagate
 export VOLUME_TIMEOUT=${VOLUME_TIMEOUT:-30}
 
-# Max time to wait for a euca-delete command to propogate
+# Max time to wait for a euca-delete command to propagate
 export VOLUME_DELETE_TIMEOUT=${SNAPSHOT_DELETE_TIMEOUT:-60}
 
 # The size of the volume we want to boot from; some storage back-ends
diff --git a/exercises/boot_from_volume.sh b/exercises/boot_from_volume.sh
index 14d0049..358b3d2 100755
--- a/exercises/boot_from_volume.sh
+++ b/exercises/boot_from_volume.sh
@@ -11,7 +11,7 @@
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
diff --git a/exercises/bundle.sh b/exercises/bundle.sh
index dce36aa..b83678a 100755
--- a/exercises/bundle.sh
+++ b/exercises/bundle.sh
@@ -10,7 +10,7 @@
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
diff --git a/exercises/client-args.sh b/exercises/client-args.sh
index 28f4123..1e68042 100755
--- a/exercises/client-args.sh
+++ b/exercises/client-args.sh
@@ -2,14 +2,14 @@
 
 # **client-args.sh**
 
-# Test OpenStack client authentication aguemnts handling
+# Test OpenStack client authentication arguments handling
 
 echo "*********************************************************************"
 echo "Begin DevStack Exercise: $0"
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
diff --git a/exercises/client-env.sh b/exercises/client-env.sh
index 147fdfc..6c6fe12 100755
--- a/exercises/client-env.sh
+++ b/exercises/client-env.sh
@@ -2,14 +2,14 @@
 
 # **client-env.sh**
 
-# Test OpenStack client enviroment variable handling
+# Test OpenStack client environment variable handling
 
 echo "*********************************************************************"
 echo "Begin DevStack Exercise: $0"
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
diff --git a/exercises/euca.sh b/exercises/euca.sh
index 7c590d0..ac21b6b 100755
--- a/exercises/euca.sh
+++ b/exercises/euca.sh
@@ -10,7 +10,7 @@
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
@@ -90,7 +90,7 @@
 
    # Test volume has become available
    if ! timeout $RUNNING_TIMEOUT sh -c "while ! euca-describe-volumes $VOLUME | grep -q available; do sleep 1; done"; then
-       die $LINENO "volume didnt become available within $RUNNING_TIMEOUT seconds"
+       die $LINENO "volume didn't become available within $RUNNING_TIMEOUT seconds"
    fi
 
    # Attach volume to an instance
diff --git a/exercises/floating_ips.sh b/exercises/floating_ips.sh
index ad11a6b..b741efb 100755
--- a/exercises/floating_ips.sh
+++ b/exercises/floating_ips.sh
@@ -9,7 +9,7 @@
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
diff --git a/exercises/horizon.sh b/exercises/horizon.sh
index 5d778c9..d62ad52 100755
--- a/exercises/horizon.sh
+++ b/exercises/horizon.sh
@@ -9,7 +9,7 @@
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
diff --git a/exercises/quantum-adv-test.sh b/exercises/quantum-adv-test.sh
index 34f4f62..abec5e4 100755
--- a/exercises/quantum-adv-test.sh
+++ b/exercises/quantum-adv-test.sh
@@ -10,7 +10,7 @@
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 
 set -o errtrace
 
diff --git a/exercises/sec_groups.sh b/exercises/sec_groups.sh
index b73afdf..6b67291 100755
--- a/exercises/sec_groups.sh
+++ b/exercises/sec_groups.sh
@@ -9,7 +9,7 @@
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
diff --git a/exercises/swift.sh b/exercises/swift.sh
index c4ec3e9..b9f1b56 100755
--- a/exercises/swift.sh
+++ b/exercises/swift.sh
@@ -9,7 +9,7 @@
 echo "*********************************************************************"
 
 # This script exits on an error so that errors don't compound and you see
-# only the first error that occured.
+# only the first error that occurred.
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
diff --git a/files/rpms/n-cpu b/files/rpms/n-cpu
index 149672a..e4fdaf4 100644
--- a/files/rpms/n-cpu
+++ b/files/rpms/n-cpu
@@ -4,3 +4,4 @@
 genisoimage
 sysfsutils
 sg3_utils
+python-libguestfs
diff --git a/lib/tempest b/lib/tempest
index 87f6a57..8b4ae0e 100644
--- a/lib/tempest
+++ b/lib/tempest
@@ -3,7 +3,7 @@
 
 # Dependencies:
 # ``functions`` file
-# ``lib/nova`` service is runing
+# ``lib/nova`` service is running
 # <list other global vars that are assumed to be defined>
 # - ``DEST``, ``FILES``
 # - ``ADMIN_PASSWORD``
@@ -78,7 +78,7 @@
     # sudo python setup.py deploy
 
     # This function exits on an error so that errors don't compound and you see
-    # only the first error that occured.
+    # only the first error that occurred.
     errexit=$(set +o | grep errexit)
     set -o errexit
 
diff --git a/openrc b/openrc
index f1026a5..adf92b9 100644
--- a/openrc
+++ b/openrc
@@ -37,7 +37,7 @@
 # The introduction of Keystone to the OpenStack ecosystem has standardized the
 # term **tenant** as the entity that owns resources.  In some places references
 # still exist to the original Nova term **project** for this use.  Also,
-# **tenant_name** is prefered to **tenant_id**.
+# **tenant_name** is preferred to **tenant_id**.
 export OS_TENANT_NAME=${OS_TENANT_NAME:-demo}
 
 # In addition to the owning entity (tenant), nova stores the entity performing
diff --git a/samples/local.sh b/samples/local.sh
index 5901525..970cbb9 100755
--- a/samples/local.sh
+++ b/samples/local.sh
@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 
 # Sample ``local.sh`` for user-configurable tasks to run automatically
-# at the sucessful conclusion of ``stack.sh``.
+# at the successful conclusion of ``stack.sh``.
 
 # NOTE: Copy this file to the root ``devstack`` directory for it to
 # work properly.
diff --git a/tools/xen/scripts/install_ubuntu_template.sh b/tools/xen/scripts/install_ubuntu_template.sh
index b7a8eff..5cbe2ac 100755
--- a/tools/xen/scripts/install_ubuntu_template.sh
+++ b/tools/xen/scripts/install_ubuntu_template.sh
@@ -37,7 +37,7 @@
 builtin_name="Debian Squeeze 6.0 (32-bit)"
 builtin_uuid=$(xe template-list name-label="$builtin_name" --minimal)
 if [[ -z $builtin_uuid ]]; then
-    echo "Cant find the Debian Squeeze 32bit template on your XenServer."
+    echo "Can't find the Debian Squeeze 32bit template on your XenServer."
     exit 1
 fi