diff --git a/wiki-rtd/docs/wiki_development/functions/compression.md b/wiki-rtd/docs/wiki_development/functions/compression.md
index 8790475..b7f5f0e 100644
--- a/wiki-rtd/docs/wiki_development/functions/compression.md
+++ b/wiki-rtd/docs/wiki_development/functions/compression.md
@@ -9,6 +9,7 @@ The shell script:
 
 With in the script there are several functions.
 
+
 ### compress_game()
 
 Description:
@@ -50,18 +51,24 @@ Description:
 ```
 
 
-## Compression targets reference list
+## Reference list: compression_targets.cfg
+
+This is used by the `find_compatible_compression_format()` function above.
 
 The reference list:
 
 [emu-configs/defaults/retrodeck/reference_lists/reference_lists/compression_targets.cfg](https://github.com/XargonWan/RetroDECK/blob/main/emu-configs/defaults/retrodeck/reference_lists/compression_targets.cfg)
 
-The config is populated with compression formats with within `[]` and what es-de folders that are targeted for the format compression.
-Each system can only have one format.
-
+The config is populated with compression formats with within `[]`.
 Each new system has to be on a new line under it's compression format.
 
-This is used by the `find_compatible_compression_format()` function above.
+Each system can only have one format and is using the es-de roms subfolders default names under `/roms/`.<br>
+
+**Example:** <br>
+You want to add `gb` to the list.
+
+- Make sure that the subfolder under roms also called the same: `roms/gb`
+- Then add the `gb` entry to under the `[zip]`
 
 ### Example
 
@@ -80,7 +87,32 @@ atari2600
 - gc is compressed to rvz
 - atari2600 is compressed to zip
 
-## How to add new system to compress
+## Reference list: zip_compressable_extensions.cfg
+
+This is used by the `find_compatible_compression_format()` function above.
+
+The [zip_compressable_extensions.cfg](https://github.com/XargonWan/RetroDECK/blob/main/emu-configs/defaults/retrodeck/reference_lists/zip_compressable_extensions.cfg) contains the list of file exstensions that can be zipped into a .zip file and used by the systems that have enabled .zip compression in the `compression_targets.cfg`. This is to make sure only supported none compressed formats are compressed.
+
+
+**Example:**
+
+List of file extensions
+
+```
+.32x
+.68k
+.NDS
+.a26
+.a52
+.a78
+.abs
+```
+
+
+## Tips on adding new system to compress
 
 1. Make sure the emulator supports the compression format and RetroDECK is using that version that supports it.
-2. Add the es-de folder name to `compression_targets.cfg` to the compression format it supports.
+2. Verify that it does work with the emulator.
+3. Make sure the system supports the compression format file format under the `<extension>` for that system in the [es_systems.xml](https://github.com/XargonWan/RetroDECK/blob/main/es-configs/es_systems.xml)  file. Otherwise it won't be found after it is compressed in the interface.
+4. Add the es-de folder name to `compression_targets.cfg` to the compression format it supports. If it is a new format that you want to compress to a .zip, add the new file extention to `zip_compressable_extensions.cfg`
+