This is the official manual for the latest Org-mode release.
Org supports links to files, websites, Usenet and email messages, BBDB database entries and links to both IRC conversations and their logs. External links are URL-like locators. They start with a short identifying string followed by a colon. There can be no space after the colon. The following list shows examples for each link type.
http://www.astro.uva.nl/~dominik on the web doi:10.1000/182 DOI for an electronic resource file:/home/dominik/images/jupiter.jpg file, absolute path /home/dominik/images/jupiter.jpg same as above file:papers/last.pdf file, relative path ./papers/last.pdf same as above file:/firstname.lastname@example.org:papers/last.pdf file, path on remote machine /email@example.com:papers/last.pdf same as above file:sometextfile::NNN file, jump to line number file:projects.org another Org file file:projects.org::some words text search in Org file1 file:projects.org::*task title heading search in Org file2 file+sys:/path/to/file open via OS, like double-click file+emacs:/path/to/file force opening by Emacs docview:papers/last.pdf::NNN open in doc-view mode at page id:B7423F4D-2E8A-471B-8810-C40F074717E9 Link to heading by ID news:comp.emacs Usenet link mailto:firstname.lastname@example.org Mail link mhe:folder MH-E folder link mhe:folder#id MH-E message link rmail:folder RMAIL folder link rmail:folder#id RMAIL message link gnus:group Gnus group link gnus:group#id Gnus article link bbdb:R.*Stallman BBDB link (with regexp) irc:/irc.com/#emacs/bob IRC link info:org#External links Info node or index link shell:ls *.org A shell command elisp:org-agenda Interactive Elisp command elisp:(find-file-other-frame "Elisp.org") Elisp form to evaluate
On top of these built-in link types, some are available through the
contrib/ directory (see Installation). For example, these links
to VM or Wanderlust messages are available when you load the corresponding
libraries from the
vm:folder VM folder link vm:folder#id VM message link vm://email@example.com/folder#id VM on remote machine vm-imap:account:folder VM IMAP folder link vm-imap:account:folder#id VM IMAP message link wl:folder WANDERLUST folder link wl:folder#id WANDERLUST message link
For customizing Org to add new link types Adding hyperlink types.
A link should be enclosed in double brackets and may contain a descriptive text to be displayed instead of the URL (see Link format), for example:
If the description is a file name or URL that points to an image, HTML export (see HTML export) will inline the image as a clickable button. If there is no description at all and the link points to an image, that image will be inlined into the exported HTML file.
Org also finds external links in the normal text and activates them as links. If spaces must be part of the link (for example in ‘bbdb:Richard Stallman’), or if you need to remove ambiguities about the end of the link, enclose them in square brackets.
The actual behavior of the search will depend on the value of
org-link-search-must-match-exact-headline. If its value
nil, then a fuzzy text search will be done. If it is t, then only the
exact headline will be matched, ignoring spaces and cookies. If the value is
query-to-create, then an exact headline will be searched; if it is not
found, then the user will be queried to create it.
 Headline searches always match the exact headline, ignoring
spaces and cookies. If the headline is not found and the value of the option
then the user will be queried to create it.