It seems fitting that one of the most used guide books in the UK was the brainwave of a woman who had got lost on her way to a party. Hard though she tried, Phyllis Pearsall could not find the London address on the most up-to-date map available. This was due to the fact that the most recent map in 1935 of the city had been published in 1919. So, armed with a notebook and pencil, and clocking up 3,000 miles, Phyllis went out on the streets of London every morning at 5am to painstakingly draw every street and walkway into a reference book. The result was the first London A-Z.

Pearsall decided to divide her new map into different sections, each of which would be coded with an index. Once they were drawn, the maps needed numerous checks for spelling mistakes, inaccuracies or omissions, as did the index. Towards the end of the process Pearsall realised that she had left out Trafalgar Square. One of her most laborious tasks was creating a job of card index for the street names. The alphabetical index inspired the origin of the A to Z logo.

Next time you need to negotiate around a complex data or file paths, spare a thought for Phyllis. Getting around a huge PDF document, for example, now takes seconds if you use Bookmarks in Adobe Acrobat 9. A Bookmark is simply a link represented by text in the Bookmarks panel. You can create your own Bookmarks, as a custom outline of a document or to open other documents. Or you can use electronic Bookmarks as you would with paper Bookmarks to mark a place in a document that you want to highlight, or to which you want to return later.

To add Bookmarks to your PDF manually, click the First Page button on the toolbar to display the first page of the document. Make sure that the Single Page button on the toolbar is selected; a Bookmark always displays a page at the magnification that was used when the Bookmark was created. In the Bookmarks panel, click the New Bookmark icon. A new, untitled Bookmark is added below whatever Bookmark was selected or at the bottom of the list of Bookmarks. Then, in the text box of the new Bookmark, type the Bookmark. Click anywhere in the Bookmarks panel to move the focus from the text box to the Bookmark.

You can even nest Bookmarks below one another to create sub-Bookmarks using simple clicking and dragging actions. You'll soon get used to dragging and positioning your Bookmarks under specific headings with a bit of practice. If you need to move a Bookmark into a correct location in the Bookmark hierarchy, simply drag the Bookmark icon directly up and above the first Bookmark in your Bookmarks list. Release the Bookmark when you see an arrow and dotted line where you want the new Bookmark to appear. You can test your new Bookmark by selecting another Bookmark to change the document window view and then selecting the new Bookmark again. And Bookmarks can be expanded and condensed so that you can hide any sub-Bookmarks if you prefer a compact look.

Bookmarks can also perform actions such as going to a website or to specific items in your document. It's easy to change the Bookmarks destination by right clicking on the Bookmark. A simple set of message commands will help you create the new Bookmark destination.

Even the appearance of your Bookmarks is under your control. The Properties command allows you to change the appearance and actions of all Bookmarks, for example, to bold, italic or colour. And remember that you can also edit the appearance of any links within your document that you are setting a Bookmark to. You can change the link type, style and even the link action.

Cross-document linking is an especially useful tool if you need to link between PDFs. You do need to make sure that any PDFs you are linking together are in the correct folder structure. It's best to keep them together in a single folder.

Remember to set your initial view settings so that your PDF opens with your Bookmarks panels displayed. To do this, click the Initial View command on the Document Properties selection on the File tab. Then, from the Navigation tab list, choose Bookmarks Panel and Page, then Save your document. And always create your Bookmarks after you have completed all editing to your PDF. Now there's no reason for anyone to give up finding their way around your PDFs.