What are filemasks?
Filemasks are filenames which contain the characters '*' and/or '?'.
What are they good for?
Filemasks are for selecting files which names correspond to the filemask. The character '*' stands for any number of any characters, while '?' stands for exactly ONE of any characters.
Any examples?
The filemask '*.txt' selects every text file which has the file extension '.txt' - e.g. 'My letter.txt', 'Shopping list.txt', etc.
If you are demanding, you should use '?oney' as filemask - this will let you retrieve 'honey' and 'money', because if you use '*oney' you will find 'boloney' and such things. But beware of '?oney*' - you would find 'Boney M.' and 'boneyard'! ;-)