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+### File Management
+#### Resume Uploading
+By clicking the upload button and re-upload the stopped file, the client will resume the uploading.
+
+#### Move Files or Folders
+You can move files or folders by following these steps:
+Choose files or folders by ticking them (in the right)
+Go to the target folder
+Click the “Paste” button at the top of the pane.
+
+#### Share Directories
+You can share a folder and its files by following these steps:
+Go to “Files” tab, 
+Go to the folder you want to share
+Click the “Share Folder” button
+
+#### Cancel Sharings
+There are 2 ways to cancel one sharing:
+In the “Files” tab, go to the folder and click the “Stop Sharing” button
+In the “Sharings” tab, find the target directory and click the “Cancel” button
+
+#### Manage Files and Folders outside the Docker Container
+If the Quickshare is started inside a docker, all files and folders are also persisted inside the docker. Then it is difficult to manage files and folders through the OS.
+ 
+Here is a solution:
+##### About Permissions
+In the Quickshare docker image, a user `quickshare` (uid=8686) and group `quickshare` (gid=8686) are predefined. Normally in Linux, you can not manage files outside the docker, because your uid is not 8686 and you are not a member of `quickshare` group. By creating a `quickshare` group and adding yourself into it, you are able to manage files:
+```
+groupadd -g 8686 quickshare
+usermod -aG quickshare $USER
+```
+
+
+##### Use [Bind Mounts](https://docs.docker.com/storage/bind-mounts/)
+You can mount a non-empty directory with uid=8686 and gid=8686 in running the docker:
+```
+docker run \
+--name quickshare \
+-d -p 8686:8686 \
+-u 8686:8686 \
+-v `pwd`/non-empty-directory:/quickshare/root \
+-e DEFAULTADMIN=qs \
+-e DEFAULTADMINPWD=1234 \
+hexxa/quickshare
+```
+Then you can find files and folders created by the Quickshare under `non-empty-directory`.
+ 
+You can also start a container with a [volume](https://docs.docker.com/storage/volumes/), however it is not easy to manage from the OS in this way.
+ 
+### User Management
+#### Add Predefined Users
+Predefined users can be added by the config file in the `users.predefinedUsers` array, for example, prepare a partial configuration file `predefined_users.yaml`:
+```
+users:
+  predefinedUsers:◊
+    - name: "user1"
+      pwd: "Quicksh@re"
+      role: "user"
+    - name: "user2"
+      pwd: "Quicksh@re"
+      role: "user"
+```
+In the yaml, 2 users are predefined: `user1` and `user2` who are identified by password `Quicksh@re`.
+Start the Quickshare by adding this configuration:
+```
+./quickshare -c predefined_users.yaml
+```
+Then you can see these users in the Settings > Management > Users.
+ 
+### System Management
+#### Customized Config
+You are able to overwrite default configuration by providing your own configuration. 
+For example, if you want to turn off the captcha, you can set `captchaEnabled` as `false` in your configuration or create a new configuration `disable_captcha.yaml`:
+```
+users:
+  captchaEnabled: false
+```
+Then start the Quickshare by appending this configuration:
+```
+./quickshare -c disable_captcha.yaml
+```
+ 
+#### Background Customization
+You can customize the background by following these steps:
+Upload the wallpaper to some directory
+Share this directory
+Copy the link of the wallpaper
+Go to `Settings > Preference` and set the Background URL in the Background Pane.
+ 
+### MISC