diff --git a/documentation/conventions.rst b/documentation/conventions.rst
new file mode 100644
index 000000000000..469ad5879b51
--- /dev/null
+++ b/documentation/conventions.rst
@@ -0,0 +1,55 @@
+.. SPDX-License-Identifier: CC-BY-SA-2.0-UK
+
+=========================
+Documentation Conventions
+=========================
+
+These conventions apply throughout the Yocto Project documentation.
+
+Placeholders
+============
+
+Text enclosed in angle brackets is a placeholder. Replace it, including the
+brackets, with a value of your own:
+
+.. code-block:: none
+
+   SRCREV:pn-<recipe> = "${AUTOREV}"
+
+Here, ``<recipe>`` stands for the name of your recipe. A placeholder is
+never text to be copied as it stands, and an example containing one will
+not work until every placeholder in it has been replaced.
+
+Commands and prompts
+====================
+
+Commands are shown with the prompt that runs them, and the prompt is not
+part of the command. Do not type it.
+
+A ``$`` introduces a command you run as your normal user:
+
+.. code-block:: console
+
+   $ bitbake core-image-minimal
+
+Where a command needs administrative privileges on your build host, it is
+shown with ``sudo`` rather than with a root prompt:
+
+.. code-block:: console
+
+   $ sudo apt install gawk
+
+A full prompt ending in ``#`` introduces a command run as ``root``, usually
+on a target machine rather than on your build host:
+
+.. code-block:: console
+
+   root@qemux86-64:~# gdb /bin/cat
+
+Within an example, a line beginning with ``#`` is a comment rather than a
+command:
+
+.. code-block:: text
+
+   # This is a comment, not a command to run as root.
+   $ bitbake core-image-minimal
diff --git a/documentation/index.rst b/documentation/index.rst
index 4bfc40bef070..72e51a4454d7 100644
--- a/documentation/index.rst
+++ b/documentation/index.rst
@@ -116,3 +116,10 @@ Release notes and migration guides for the different Yocto Project releases.
    :hidden:
 
    downloads
+
+.. toctree::
+   :maxdepth: 1
+   :caption: Documentation Conventions
+   :hidden:
+
+   conventions