How to upload a file
If you wish to include a file--most often it will be a picture--in the article you are writing or editing, you have to upload it first. You can do that by navigating to the left sidebar and using the Upload file link. You will see this form:
To upload a file, select with the Procházet... button. (Or Browse... if you use English language.) Select the file you want to upload. You can change the destination filename if you don't want to use the original name of the file you are uploading.
It is good to include a short description of what the file is (i.e. what is displayed on the picture).
If you are uploading copyrighted work, please add the source of the work in the description as well!