The following is the list of options available for Twitter's tweet button
Enable Twitter button
This is the global switch for Twitter's button.
Via @
When your user's click the button it will have the "Via @<user>" according to your configuration. Do not include the @.
Recommend @
When your user's click the button it will recommend a user according to your configuration. Do not include the @.
Hashtag #
When your user's click the button it will include a hashtag according to your configuration. Do not include the #.
Language
Twitter's button language.