I do it all the time.
I was bored... I was following a thread and the zip thing was mentioned. I wondered about sharing a layer as a *.lpkx but I thought, NAH! if it ended in zip we would be done, zip the shapefile and off you go via email or the cloudie sharsies thing that is so popular.
PKzip and 7-zip are 2 popular zip programs out in the domain, so I thought why not have a look.
Besides 7-zip's 7z.dll can be seen in C:\_install_folder_\bin, so maybe it is installed besides my already installed version. Opening up an *.lpkx file confirmed my suspicions 7z! BTW, there are webpages listing what to look for as magics in the first number of bytes of a file, but that is for another blog.
![package_layer00.png package_layer00.png](https://community.esri.com/t5/image/serverpage/image-id/29309i95CB208B593B97CE/image-size/small?v=v2&px=200)
So I unpacked my layer file to see what was in the layer package.
The next 2 images show the process of making the layer package.
![package_layer01.png package_layer01.png](https://community.esri.com/t5/image/serverpage/image-id/29314i28CFBCB1209F426B/image-size/small?v=v2&px=200)
![package_layer02.png package_layer02.png](https://community.esri.com/t5/image/serverpage/image-id/29315iA381B5FFDD3B6F1F/image-size/small?v=v2&px=200)
Then I gave it a shot of seeing what was inside using 7-zip
![package_layer03.png package_layer03.png](https://community.esri.com/t5/image/serverpage/image-id/29317i409BF5C123DB55F0/image-size/medium?v=v2&px=400)
And to my surprise there was a whole bunch of stuff inside, and the sample shapefile I used was contained in a folder. The other folders had other stuff in them which might have been useful to some
![package_layer04.png package_layer04.png](https://community.esri.com/t5/image/serverpage/image-id/29316iBF3A696AC2FF10CD/image-size/medium?v=v2&px=400)
So not everything appears to be what it is. For instance, did you know that Word's *.docx format is really a zip file at its first level?? Look for the PK at the start of a word file in a text editor.
Now on to explore other things that might just be compressed.
Back! works for packed projects even packaging my gdb and toolboxes
![package_layer05.png package_layer05.png](https://community.esri.com/t5/image/serverpage/image-id/29342i4E1827A6964394B6/image-size/medium?v=v2&px=400)