Netscape Navigator's extensions to HTML include an extension called "frames." Microsoft Internet Explorer also recognizes these. You can create frames to divide a browser window into different panes of information which can be viewed and changed independently.

The new elements to implement frames are FRAMESET, FRAME, and NOFRAMES. The attribute Target of the A (anchor) element is also added. An example frameset file can demonstrate this (you'll need a Netscape 2.0 browser to view this).

Here's the details of the syntax:

• FRAMESET: this element is the container for a frame; instead of having a BODY element, a frame document uses FRAMESET. This element can be nested.
  Attributes:
  • Rows = "row_height_value_list": a comma-separated list of values indicating the height of each of the rows.
    • If a number, the row is that high in pixels;
    • If a number followed by a %, the row gets that percent of the total window height;
    • If a *, the row gets the remaining room;
    • If a number followed by a *, that row gets that much more share of the height;
  • Cols = "col_width_value_list": a comma-separated list of values indicating the width of each of the columns. The values are the same syntax as for the Rows attribute.
• FRAME: this element identifies a single frame in a frameset.
  Attributes
  • Src = "url": The url refers to the resource to be initially displayed in this frame.
  • Name = "text": assigns a name to the frame; this name then can be used in other documents in the Target attribute of the anchor element.
  • Marginwidth = "value": The number of pixels to add to the left and right of the contents of frame the frame.
  • Marginheight = "value": The number of pixels to add to the top and bottom of the contents of frame the frame.
  • Scrolling = "yes | no | auto":
    • yes = add scrollbars, even if they are not needed;
    • no = NEVER add scrollbars even if they are needed;
    • auto = add scrollbars if they are needed; (default)
  • Noresize: a flag that indicates the frame is not resizable by the user; Normally, a user can manually alter the size of the frame using "grab buttons" that appear on the display of the frame. The Noresize attribute makes this resizing impossible.
• NOFRAMES: this element brackets content that will be rendered by non-frame-enabled browsers.
• A (anchor element): the attribute Target is added. This attribute defines in which frame the new content referenced in the anchor will be displayed when selected. Target has the possible values:
  • name: a frame named in a FRAME element's Name attribute;
  • _self: new document is displayed the in same frame as the anchor that loads it; this is the default;
  • _parent: displays the new document in the parent frame; if no parent, same as _self;
  • _top: displays the new document in the entire window; if no frames, same as _self;
  • _blank: display the new document in a new, unnamed window;
• BASE element, includes a new attribute, Target, which lets you set the default target for every hypertext link in the document. Its possible values are the same as for the Target attribute of the A element.

More Information and examples of frames:

• Frame Information from Netscape
• Anatomy of an Eye, an example application of frames, from Netscape