34.4 Using the Gnus Summary Buffer
The following commands are available in the Gnus summary buffer:
SPC​
If there is no article selected, select the article on the current line and display its article buffer. Otherwise, try scrolling the selected article buffer in its window; on reaching the end of the buffer, select the next unread article (gnus-summary-next-page).
Thus, you can read through all articles by repeatedly typing SPC.
DEL​
Scroll the text of the article backwards (gnus-summary-prev-page).
n​
Select the next unread article (gnus-summary-next-unread-article).
p​
Select the previous unread article (gnus-summary-prev-unread-article).
s​
Do an incremental search on the selected article buffer (gnus-summary-isearch-article), as if you switched to the buffer and typed C-s (see Incremental Search).
M-s regexp RET​
Search forward for articles containing a match for regexp (gnus-summary-search-article-forward).
M-r regexp RET​
Search back for articles containing a match for regexp (gnus-summary-search-article-backward).
q​
Exit the summary buffer and return to the group buffer (gnus-summary-exit).