I've found in the filter help following textL "To discover module names and deltas, visit admin/build/block and hover over a block's configure link and look in your browser's status bar. The last "word" you see is the name of the module and the number following that is the delta."

However delta can be not numeric, for ex. in views and sharethis module. User should call sharethis block in a way like this: 

[block:sharethis=sharethis]

Comments

dealancer’s picture

dealancer commented

Please update this description.

nancydru’s picture

nancydru
she/her/hers
Primary language English
Location Boston
commented

Indeed, take a look at the schema for the blocks table. Delta is varchar, not int. I consider it good practice to name blocks with text rather than numbers (see Weblinks).