Editing Wikitext/Templates Ready to Use

Introduction.
This page introduces a few "existing" templates, and others can be found:
Writers are encouraged to add links for useful Wikibooks templates, perhaps in tabular form within these or other sections. 
Hidden Contents.
Sometimes a page gets a bit cluttered. Much "detailed" information is best tucked away where it can be accessed when needed, but where it does not detract from what is being said.
For this purpose there are templates such as or . The quoted example presents a neat box with a heading and a link. The link toggles; left-clicking it the first time drops the box to show the contents. Clicking the link again closes the box. The amount of content can be considerable. Notice that whereas Dropimage can be narrower than the page, the template FullWidthPage is made to occupy it fully at all times.
Despite their names, both boxes also can contain text or other elements, including other templates. For Dropimage and FullWidthDrop, HTML tables are preferred to Wiki ones.
Examples of the use of Dropimage are shown below for an image, for text and for an HTML table. Further examples of its use can be seen throughout the Editing Wikitext series.
Image Templates.
Images cannot include captions unless the image syntax makes use of a "frame" or a "thumbnail". Borders tend also to be of a standard format and cannot ordinarily be customised. 
These limitations are overcome by using the set of templates , , , and . A brief inspection of their names shows that there one for each of the standard image positions. These templates also have a number of options.
An example of the captioning is given with the image on the left, and can also be seen on the page The Quick Course.
Users of Internet Explorer will find that the mouseover functions do not work for them. 
Images are usually fixed on the page but there is a technique that allows "two" images to occupy the same space. An example is shown on the right. When the mouse moves over the image, a different image is shown instead. It is designed by persons more clever than me as a template. The whole thing allows the use of the standard image options, and the template is called .
HoverImage's first two parameters are the "file names" of the two images to use; the first is the default image and the second is the alternative. There are separate caption options too; they are written in the same sequence as the image names. The other options like "position", "size", and "type of border" can be added and apply to both images at once. The template can be used in places where a normal image syntax line is used. The code to make the hover-image on the right is just:
If the template is used for images with different shapes, some improvement is achieved by setting the height exactly and by setting the base dimension as some impossibly high value; in this way both images will be set to the intended height. Note also that the entire template can become the "content" of the template, and still works well; in this event set the image option to "center".
The unwanted white border in the image example is not a fault in the template but is a consequence of using images with frames on a colored page background; it is a bug. To avoid this, simply use a frame-less image. If a caption is needed as well then use the HoverImage template as the image parameter of e.g., "Noframeleft", to make a frame-less image "with" a single caption. The image on the "left" was made in this way. The coding for mouse-hover frameless images with a single caption is just:
Information Boxes.
There are many information boxes available within Wikibooks. The majority of them find use for administrative comments and reminders. The background color and the text alignment are options. As is clear from the above examples, the text can also contain hyperlinks. 
Highlight Blocks.
The above example shows another box, this time made with the template to emphasise the code lines that need to be learned for some context or another.
It uses a Courier font for programming and mark-up code descriptions. It is intended for single lines though it will expand, and background color, font, alignment, and other elements are options.
At a more general level, the template can be used for page-building. When one instance of the template immediately follows another, color banding becomes possible. Since it is based on the "div tag" it has very few differences from the main page.
A version called also exists to be contained in sections of text that wrap left or right. This was needed to overcome a bug, where "divs" insist on using the full width of a page.
The template "Block" stacks neatly top to bottom for page-building like this:
Banded Bullet Points.
Although this set of templates lacks elegance it has been found to save time over the more laborious method that involves a custom table. The template call for the above example uses a custom width and position and looks like this:
Hidden Headings.
As will no doubt be known, every heading in a Wiki is listed as a link in the table of contents. 
Sometimes, there is no need for a table of contents entry, but a heading is still needed. This is one way to avoid too many levels within the contents box. For this purpose, the set of six templates through has been made to imitate the heading styles.
For example, the use of "Hiddenh3" corresponds to a "level three" heading in Wiki, and an "h3" heading in HTML. Use them, for example, within drop-boxes, where otherwise closed boxes might cause listing confusion. Because they are not taken formally as listings, it will not be possible to link to such headings as would otherwise be the case. 
Drop Capitals.
drop capital is this big letter at the start of the paragraph. It is sometimes used in art work or to start stanzas in prose, though at the most general level, it finds use where there is no formal heading style. It is a form of text emphasis, in that it directs attention to the start of a section.
The example uses the template . It is only the first letter that is contained in the template call, and in every case, the next text character, (ignore any space), is typed hard left against the template's closing brackets.
For those who need a more complicated format of their own, it will be necessary to make one, since as far as is known, this is the only one on file. A point worth noting is that drop capitals are unlikely to line up vertically, unless a mono-spaced font is found for the purpose. For this reason they tend to be used far enough apart to avoid the discrepancy. 
Writers' Data Lists.
While working on a page there is often some CSS code or color format that needs reference. To avoid the need for page-searching a number of templates containing such information can be placed adjacent to the work, on the page or sandbox, ready for use. The lists are compact since they are hidden in drop-boxes until they are needed. The list so far includes these: