Gnus Marks

Gnus

For marks in the summary buffer, see Section 3.7.2 in Gnus manual

u will mark ticked

Shift-3 will set the process mark on an article

M-u or d will unmark ticked

M P R will set process marks according to a regular expression.

gnus-summary-execute-command can run a random command on articles whose headers match regular expressions. If you use the Shift-3 command, you can mark articles with the "#" based on regular expressions in any header (or the whole body if you want)