Questions

One license to read the book, from one of two places. Here, $24.99: the online reader, an EPUB made for you for any reader app, and twelve months of monthly drops. On Apple Books, $31.99: the book in the Books app, with every drop for as long as it is listed there. Neither one is a subscription.

No, in either place. Here: you pay $24.99 once, drops are included for twelve months from the day you buy, and when they end you keep the last drop you received; $19.99 adds another twelve months whenever you like, and nothing renews by itself, ever. On Apple Books: you pay $31.99 once, and Apple delivers every drop for as long as the book is listed there.

Here: by card, through Stripe; the card details go to Stripe and never touch this site, and promotion codes, when there are any, go in at checkout. On Apple Books: with the payment method on your Apple ID.

Here: the book opens, and a receipt with a sign-in link goes to the email you paid with; that email is your account, and next time you choose Sign in and enter it, or set a password under Account. On Apple Books: the book appears in your Books library, the way any Apple Books purchase does.

Buy it with their email at checkout and the account is theirs; the receipt and sign-in link go to them. Do not buy it with your own email and pass the sign-in on: the license is one reader, and shared sign-ins close the account.

Because it changes every month and Kindle cannot deliver that. When a Kindle book is revised, only new buyers get the new version; people who already bought it keep the old one. Here and on Apple Books, every buyer gets every drop.

No. They are separate purchases of the same book, and most people need only one. The side-by-side page shows what each one is.

The monthly release of the book. On the 25th of each month the book is re-read against X's published code, X's rules and program terms, X's monthly enforcement report, and fresh numbers from live accounts measured through the X API. The new version drops, and an email tells you what changed.

No. Here, the online book is already the new drop, and if you keep the EPUB on a device you download it again to replace the file there. On Apple Books, Apple updates the book in your library.

X has no schedule of its own. Its code changes when its engineers push changes, its help pages change when they change, and its Under the Hood enforcement report lands around the 9th. The 25th gives time to read all of it and re-measure before the drop.

The drop on the 25th covers it. Drop dates are targets, not promises: a drop can be late, or smaller than usual, if X changes something large or takes something away; the terms say exactly what can end or delay one.

The Drops page on this site lists every drop with its notes, and the same timeline shows what X pushed and when. Here, your account page also shows the drop you are on and the date your drops run through. On Apple Books, the "What's new" notes on the book carry the same list.

This applies to purchases here only; Apple Books has no twelve-month term. Here, you keep the last drop you received: online, and the file. If you want the newer drops, $19.99 adds twelve more months from that day, and your copy becomes the latest drop at once.

No. The reader runs in any browser on any device, and remembers your page across all of them.

Select the words and pick one of six colors. Click a highlight later to change its color, add a note, or remove it. A highlight can run across paragraphs, up to about a page.

Click a highlight, choose Note, and write. A small dot after the highlight shows there is a note; click the dot and it opens. Notes can also be added to bookmarks, from the Marks panel.

Every page has a ribbon at its top-right corner. Click it to bookmark the page; click it again to take the bookmark off.

The panel that lists every bookmark, highlight, and note you have made, with its chapter and page. Click one and the book jumps there.

Yes. They are tied to the words, not the page numbers, so when a new drop moves the pages they find their places again. If a passage was rewritten and cannot be found, the highlight stays in the list marked as not found, so nothing disappears silently.

No. They are yours alone, never shared, never shown to anyone, and never used for anything.

Yes. The sun and moon in the top bar switch the site and the book together.

Yes. The minus, Fit, and plus buttons zoom the page. Fit fills the window.

Yes. The sample opens the same reader with the front of the book, all of Chapter 1, and the start of Chapter 2, and the highlights, notes, and bookmarks all work in it. Whatever you mark in the sample stays in your browser and is cleared when you buy.

An EPUB, the standard ebook format, made for you. It opens in Apple Books, Google Play Books, Kobo, Calibre, Thorium, and any reader app, and it can be sent to a Kindle.

Download the EPUB, then go to amazon.com/sendtokindle and drop the file in, or email it to your Kindle address. It shows up on the Kindle within a few minutes.

Every file is made for one reader. It carries your name and email on the copyright page and a copy identifier in the text. Keep it on as many of your own devices as you like. A copy that is passed to someone else leads back to the account it came from, and that account is closed.

Yes, as often as you like. Under Downloads, download it again and the new file replaces the old one on your device.

Choose Sign in and enter the email you bought with; a link comes by email and works once. Or set a password under Account and use that. Or use Continue with X or Google, if that is the same email address.

Look in spam or promotions, and check that you entered the email you paid with. The link is good for twenty minutes; ask for a fresh one if it has passed. If you bought on Apple Books, the book is in the Books app, not here.

Yes, under Account. A confirmation link goes to the new address, and the change is made when you open it. If you have a password, you enter it first.

Write through the contact form from the address you can reach, with the name on the card and the date, and it is moved.

Yes. Sign in on each; the reader keeps your place on all of them. An account can stay signed in on up to six devices; the oldest drops off when a seventh signs in.

Under Account, "Sign out everywhere else" signs every other device out and cancels unused sign-in links. Changing your password does the same.

It is the same book in the Books app on iPhone, iPad, and Mac, with the app's own highlights and notes, for $31.99. Apple delivers every drop for as long as the book is listed there, and Apple handles the purchase and any refund. It does not include an account here, the online reader, or the site's file.

Not by itself: Apple never tells this site who bought, so there is no account to sign in to. The book, the drops, and Apple's highlights are all in the Books app.

Download your EPUB and open it on an iPhone, iPad, or Mac; it goes straight into the Books app and stays in your library. That is your copy, not the Apple Books edition, so drops arrive by downloading the new file rather than through Apple.

Here: the book is a digital file you can open at once, so the sale is final once you have opened it online or downloaded the file; if it will not open at all, write within 14 days and it is fixed or refunded in full. On Apple Books: Apple handles refunds, at reportaproblem.apple.com, under Apple's policy.

Reading the book yourself, online and on your own devices, as often as you like. Not selling, renting, sharing, posting, or giving the book or its file to anyone, not sharing your sign-in, and not copying the text into another product, course, or publication.

The file carries your name and a copy identifier, so a shared copy leads back to your account, and the account is closed: no sign-in, no reader, no downloads, no refund.

No. It explains X's published code and rules; it does not guarantee any result, any number, or admission to any X program. X decides who is admitted and paid. The terms say this in full.

Your email, your name if you give it, your purchases, your reading position, and your highlights and notes. Payment details stay with Stripe. Visitors are counted without cookies. Nothing is sold or shared for marketing, ever. The privacy page lists everything.

Drop and renewal emails, yes, under Account. Receipts and sign-in links still come, because they are how the book reaches you.

Yes. Write from the address on the account and everything is deleted. That ends access to the book.

No. It is written for people who have never read a line of code. Every term is defined the first time it is used, and every number says where it came from.

Four places: X's published feed code, all of it; X's written rules, program terms, and help pages; X's monthly Under the Hood enforcement reports; and live accounts measured post by post through the X API. The book says which one each number came from.

No. It is not made, endorsed, sponsored, or reviewed by X Corp. X's code is quoted from X's public repository under its open-source license.

Bill G. Wolcott. The About page in the book says the rest.