# Conventions

The following admonitions will be found throughout the book:

A note presents interesting, sometimes technical, pieces of information related to the surrounding discussion.

A tip offers advice or an easier way of doing something.

A caution alerts the reader to potential problems and helps avoid them.

A warning advises the reader of a hazard condition that may arise in a given scenario.

Cross-reference conventions for print will be displayed as follows:

- Internal references will look like this: . The numeral contained within square braces is the [page number].

- External references, such as those pointing to a Web site, will look like this.

PDF, HTML, and XHTML versions of this document will use hyperlinks to handle cross-referencing.

Type conventions will be displayed as follows:

- File names or paths to directories will be shown in `monospace` type.

- Commands that you type at a prompt will be displayed in `bold` type.

- Options that you click, select, or choose in a user interface will look like this.

- When variables, parameters, SGML tags, etc. are contained within a paragraph of text, they will be shown in `monospace` type. Otherwise, they will use the normal type.

Menu selections, mouse actions, and keyboard short-cuts:

- A sequence of menu selections will be displayed as follows: File Open

- Mouse actions shall assume a right-handed mouse configuration. The terms click and double-click refer to using the left mouse button. The term right-click refers to using the right mouse button. The term middle-click refers to using the middle mouse button, pressing down on the scroll wheel, or pressing both the left and right buttons simultaneously, based on the design of your mouse.

- Keyboard short-cut combinations will be displayed as follows: Ctrl N. Where the conventions for Control, Shift, and Alternate keys will be Ctrl, Shift, and Alt, respectively, and shall mean the first key is to be held down while pressing the second key.

Code conventions:

- Code and mark-up samples will be formatted in a grey block.

- Sometimes, lines of code or mark-up examples will be longer than the page width. To avoid having them run off the page, the slash character "\" is used to denote a soft line break. This means that the line of code is meant to be on one line, but for print formatting, it has been broken across two or more lines.