Important note or instruction.

Warning about possible errors or important notes to which you should pay special attention.

Anti-virus network

A new term or an accent on a term in descriptions.

<IP-address>

Placeholders.

Save

Names of buttons, windows, menu items and other program interface elements.

ctrl

Keyboard keys names.

/Volumes/Macintosh HD/

Names of files and folders, code examples.

Appendix A

Cross-references on the document chapters or internal hyperlinks to web pages.