Template:Flag data/doc is an internal data container not intended to be transcluded directly. It is used indirectly by templates such as flag, flag icon, and others.

This template is transcluded if a flag template is used without the first parameter, or with an empty first parameter. It can be used to place an "invisible" flag icon, as an alternative to using {{noflag}} (which adds a <span> tag with padding at the size of a flag icon), if one item in a list of items with flags shouldn't have a flag icon. For example:

which looks the same as

Comparison: with and without flag

edit

For further instructions, please see: WikiProject Flag Template.