A link is a piece of text which has a hidden internet directive.  The link, as a hidden URL or Uniform Resource Locator, is not normally displayed to the reader, nor in the online editors normal display.  If the visible text is the exact text of the URL, or contains the URL, then the URL is made obvious, but it is the hidden version of the URL that is used to activate an internet server request. The visible text is usually displayed in a different color, style or font , to distinguish itself from the surrounding text, and this style may vary depending on wether the browser has already visited the link, or if the mouse pointer is over or away from the link.

Most URLs in web browsers have the service indicator "http:" at the beginning and clicking on them performs a "Get" request of a document from the indicated server. Other examples of service indicators include "ftp:" and "mailto:".

The hidden text format of the URL is something like http://server.subdomain.topdomain/document/path?parameter1=arg1&parameter2=arg2& . . .

The first part after the service name after the // is a server name with its full domain name, that must be resolved into a numeric server internet protocol (IP) address (a 4 byte address for IPv4, or a 16 byte address for IPv6). We do not concern ourselves with IP address, because these are automatically looked up by the internet system using the server domain name.

If a link refers to another document path on the same server as the browser document it is found in, the service and server name is omitted.  The link is then an absolute path to a document on the same server if it begins with a '/', or it is a relative path otherwise.

In order to insert a link while editing a web page, using the online editor, find the symbol for a link in the menu, usually showing a small icon of a chain segment. 

In the tinymce editor used to create this page, the tool tip flashes a small help text telling of the purpose of the icon, when the mouse pointer is placed over the menu icon.  The drop down Text Menus can also be used to bring up the item.

Either way results in a small link editor window which pops up as a child of the current web browser page.

This window can also be opened with the information from an existing link on the page, if the text of that link was already selected.

That's it really, all that is necessary to do now is copy and paste, or enter the text of the URL.  The 'Text to display' may have been preselected already, or will be blank if no selection existed prior to opening the link editor.  The title shows up like a tool tip, and target can be be changed to instruct the browser to always open the link in a new window. For instance this following link should open a duplicate of this page, as an absolute path to read-only output form on the same server.

On this server, url path segments do not represent paths in the server file system. The path is translated into a /controller/action/argument format.  Hence "/blog/edit/3" is the editable page that can be accessed only by a logged in user with the Editor role. The format "/read/article/3" shows the page as it can be seen for public access since the last save from the edit window. There are no relative URL's and all links to files and pages on this server are entered starting with a '/'.

Links to other servers must be entered in full, starting with the 'http://'.