How to use this book

Everything the book can do, in the order you are likely to need it. Five minutes to read, and you do not have to remember any of it, because every control says what it is when you tap it.

Put it on your home screen first

Do this once and you never think about it again.

1. Open the book on your iPad in Safari. The address is tasar1-ship-it.github.io/49er-theory-book/ and you should see the dark blue cover with a gold Start button.
2. Tap the Share button, the square with an arrow coming out of the top, scroll down the list, and tap Add to Home Screen, then Add. A book icon appears on your home screen.
3. From now on open the book from that icon rather than from a Safari tab.

This matters more than it sounds. A page left in a Safari tab can have its saved highlights wiped by the iPad after a few weeks of not being opened. A book opened from its own icon does not. It also means the whole book works with no signal at all, so you can read it in the boat park.

Moving around

Contents, top left, is the list of all nineteen chapters.

The chapter title in the middle of the top bar is a button. Tap it and the list of that chapter's sections slides up with the one you are reading marked. Tap any section to go straight there. The same panel carries the previous and next chapter at the bottom, so you can move on without scrolling to the end of the chapter first.

The thin gold line across the very top shows how far through the chapter you are, so the length of what is left is visible rather than guessed. The number beside the chapter title is the section you are in at that moment, and it changes as you scroll.

Making it comfortable to read

Aa, top right, opens the reading settings. Text size has four steps; use the largest on the water. Background has three: Bright for daylight, Sepia which is easier on the eyes for a long sitting, and Dark for night. The third setting picks the voice used by the spoken walkthrough.

Dark, beside Aa, switches between bright and dark in one tap without opening anything. All of this applies to your iPad only and changes nothing for anyone else.

At the top of the contents page there is a gold button with a play triangle on it, reading Listen to how this works. It reads a short walkthrough of the book aloud, and tapping it again stops it.

When you do not understand something

Phrases with a dotted underline are explained. Tap one and a panel opens saying what it means in plain terms, what it does on the boat, and where the idea runs out. There are more than a hundred of them, including one for each control: the cunningham, the outhaul, the vang, mast bend, rake, rig tension, the halyards, and what moves the centre of effort.

Each panel carries two more buttons. Still not clear sends a request for a better explanation of that exact term into your marks list. All terms opens the glossary, which is every explained phrase in one place.

Tags such as S12 are sources. Tap one and it shows the book or document it came from and links to it, so you can check anything you doubt. Nothing here carries a tag unless the source really says it.

Where the book says crew value, that is a number nobody has published for this boat. It is yours and Antonio's to measure and write in. It is deliberately blank rather than guessed.

Marking as you read

Select any words with your finger and a small dark bar appears with four coloured circles and three words.

The four circles are four kinds of highlight. Yellow means important, remember this. Blue means I do not understand this yet. Green means agreed, this matches what we already do. Red means I disagree, or this is wrong for our boat.

One tap on a circle and the passage is marked in that colour. That is the whole thing. The colour travels with the mark all the way into what is sent on, so a blue passage and a red one get answered differently.

Beside the circles, Note saves a highlight with something written on it for yourself, Ask sends a request for more on that passage and offers a list of what kind of more, and Copy copies the passage.

Tap any highlight you have already made to open it. From there you can change its colour, edit the note, delete it, or email the request. At the foot of every chapter there is a request button for the chapter as a whole rather than for one passage.

Your marks list

Marks, top right, is everything you have marked, grouped by chapter, with the key to the four colours at the top and a grey box telling you whether your marks are safe.

The button reading Everything is a filter. Change it to see only highlights, only notes, only requests, or only one of the four colours. Filter to blue and you have a list of everything you did not follow, which is the most useful list in the book. Every mark has Open in the book, which takes you back to the exact passage, and Delete.

Keeping your marks safe

Your highlights live on your iPad and nowhere else. If it is lost or wiped they are gone, unless you have made a copy. The grey box at the top of the Marks page tells you which of those two you are in, every time you look.

1. Tap Marks, then Back up. The share sheet opens.
2. Tap Save to Files, choose iCloud Drive, and save. The grey box then reads "Backed up today. Nothing new since."

Do it again whenever the grey box says there are marks since the last backup. Once a session is plenty.

If you ever lose everything, tap Restore. It takes the backup file, or the text of any marks email you have sent, and puts them back. Restoring only ever adds, so it can never overwrite something newer you have written. The one consequence is that a mark you deleted after a backup will come back, which is the right way round for a safety net.

Never clear website data or history for this site to fix a problem. That is the one action that deletes your highlights for good. When the book has been updated and you cannot see the change, close it completely instead: swipe up from the bottom of the screen and swipe the book away, then open it again from the icon.

Sending your marks on

Email to Ronald on the Marks page writes the whole list into an email, already addressed, and opens your mail app. You tap send. Nothing leaves the iPad until you do. Export saves the same list as a file, and Copy all puts it on the clipboard to paste into a message instead. Whichever you use, the colours and the requests come through, so a blue highlight arrives as "did not understand this" rather than as a highlighted sentence.

The small print, which is short

Everything you mark stays on your own iPad. Nothing is sent anywhere until you press a button that says it will send. There is no account and no login.

You and Antonio never see each other's marks. There is no shared list. It is not that they are hidden from each other: they are on different iPads and there is nothing joining them.

What is here, and what is not yet

All nineteen chapters carry the explanation panels, the section jump, the glossary and the sources. Only chapter 3 has figures so far; the rest are text, and the figures are being drawn chapter by chapter once chapter 3 has been judged.

Five sections are waiting on voice notes that have not arrived: 6.1, 8.6, 13.6.1, C.2 and C.3. They are written as they stood and will be revised when the notes come in.