diff --git a/docs/markdown/Compiler-properties.md b/docs/markdown/Compiler-properties.md
index 5978b5d51..06efff38f 100644
--- a/docs/markdown/Compiler-properties.md
+++ b/docs/markdown/Compiler-properties.md
@@ -29,26 +29,9 @@ Compiler id
 ==
 
 The compiler object has a method called `get_id`, which returns a
-lower case string describing the "family" of the compiler. It has one
-of the following values.
-
-| Value     | Compiler family                |
-| -----     | ----------------               |
-| gcc       | The GNU Compiler Collection    |
-| clang     | The Clang compiler             |
-| msvc      | Microsoft Visual Studio        |
-| intel     | Intel compiler                 |
-| llvm      | LLVM-based compiler (Swift, D) |
-| mono      | Xamarin C# compiler            |
-| dmd       | D lang reference compiler      |
-| rustc     | Rust compiler                  |
-| valac     | Vala compiler                  |
-| pathscale | The Pathscale Fortran compiler |
-| pgi       | The Portland Fortran compiler  |
-| sun       | Sun Fortran compiler           |
-| g95       | The G95 Fortran compiler       |
-| open64    | The Open64 Fortran Compiler    |
-| nagfor    | The NAG Fortran compiler       |
+lower case string describing the "family" of the compiler. See
+[reference tables](Reference-tables.md) for a list of supported
+compiler ids.
 
 Does code compile?
 ==
diff --git a/docs/markdown/Reference-tables.md b/docs/markdown/Reference-tables.md
new file mode 100644
index 000000000..b604fb691
--- /dev/null
+++ b/docs/markdown/Reference-tables.md
@@ -0,0 +1,60 @@
+# Reference tables
+
+## Compiler ids
+
+These are return values of the `get_id` method in a compiler object.
+
+| Value     | Compiler family                |
+| -----     | ----------------               |
+| gcc       | The GNU Compiler Collection    |
+| clang     | The Clang compiler             |
+| msvc      | Microsoft Visual Studio        |
+| intel     | Intel compiler                 |
+| llvm      | LLVM-based compiler (Swift, D) |
+| mono      | Xamarin C# compiler            |
+| dmd       | D lang reference compiler      |
+| rustc     | Rust compiler                  |
+| valac     | Vala compiler                  |
+| pathscale | The Pathscale Fortran compiler |
+| pgi       | The Portland Fortran compiler  |
+| sun       | Sun Fortran compiler           |
+| g95       | The G95 Fortran compiler       |
+| open64    | The Open64 Fortran Compiler    |
+| nagfor    | The NAG Fortran compiler       |
+
+## Script environment variables
+
+| Value               | Comment                         |
+| -----               | -------                         |
+| MESON_SOURCE_ROOT   | Absolute path to the source dir |
+| MESON_BUILD_ROOT    | Absolute path to the build dir  |
+| MESONINTROSPECT     | Command to run to run the introspection command, may be of the form `python /path/to/meson introspect`, user is responsible for splitting the path if necessary. |
+| MESON_SUBDIR        | Current subdirectory, only set for `run_command` |
+
+## CPU families
+
+These are returned by the `cpu_family` method of `build_machine`,
+`host_machine` and `target_machine`. For cross compilation they are
+set in the cross file.
+
+| Value               | Comment                         |
+| -----               | -------                         |
+| x86                 | 32 bit x86 processor  |
+| x86_64              | 64 bit x86 processor  |
+| arm                 | 32 bit ARM processor |
+
+Any cpu family not listed in the above list is not guaranteed to
+remain stable in future releases.
+
+## Operating system names
+
+These are provided by the `.system()` method call.
+
+| Value               | Comment                         |
+| -----               | -------                         |
+| linux               | |
+| darwin              | Either OSX or iOS |
+| windows             | Any version of Windows |
+
+Any string not listed above is not guaranteed to remain stable in
+future releases.
\ No newline at end of file
diff --git a/docs/sitemap.txt b/docs/sitemap.txt
index af8aede5b..755daacda 100644
--- a/docs/sitemap.txt
+++ b/docs/sitemap.txt
@@ -47,6 +47,7 @@ index.md
 		Creating-OSX-packages.md
 		Creating-Linux-binaries.md
 	Reference-manual.md
+	Reference-tables.md
 	FAQ.md
 	Reproducible-builds.md
 	howtox.md