A great selling features of the Apple iPad is iBooks, the app and online store that turns the iPad into an eBook reader. You do NOT have to buy eBooks from Apple’s iStore to read eBooks on the iPad. Other eBook formats are supported by the Apple iPad. The follow is a great list:
ePub – is an open ebook format that is used by many online stores. You can also convert other formats to ePub and then sync them to the iPad via iTunes.
PDF - (Portable Document Format) is the reigning downloading document format on the website, so you’re likely to find ebooks in this format. The iPad lets you load PDFs onto your iPad and read them via third-party apps.
iBooks – the books purchased through the iBooks Store are actually in ePub format, but include DRM to prevent unauthorized sharing or copying.
Kindle - Amazon’s Kindle isn’t just an ereader that competes with the iPad, it’s also an ebook format. Though you can’t read Kindle books through the iBooks apps, you can read them on the iPad using Amazon’s Kindle app.
Barnes & Noble – Just like with Amazon, Barnes & Noble has an app that lets you buy read books purchased from their online store on the iPad.
Here is a helpful article I found, Let me know if you like it:
When Apple’s executive Steve Jobs presented the brand new iPad to the press and demonstrated many of its features, he also remarked that the iBooks application for iPad will use the increasingly popular EPUB format – a free format that was launched by the International Digital Publishing Forum.
Many publishers and authors are turning to EPUB format due to its increased use, and it is now possible to format and edit electronic books in EPUB with either a PC or a Mac computer – using tools such as the Sigil EPUB editor software or the iStudio Publisher desktop publishing application.
While EPUB offers powerful solutions for writers and publishers, some critics do point out that it is not ideal for publications that are heavily graphics-driven and have complex layout requirements. Comic books are one example that comes to mind, but even those who point out the EPUB’s weakness in that specific area of publishing acknowledge that it is becoming such a widely used format that EPUB will likely be upgraded.
With companies as influential as Apple behind the product, it definitely looks like EPUB is here to stay and will only be improved over time as more people take advantage of it and insist on features to facilitate their publication requirements. EPUB is a format already used by many people on the new iPad, the iPhone and iPod touch, for example.
Meanwhile many new types of ebook readers are being unveiled, and as soon as Apple launched its much anticipated iPad lots of competing companies announced that they, too, would be offering consumers products that are essentially similar to the iPad. As the world of technology focuses its attention on capturing a share of the booming ereader and ebook market, consumers will be the big winners and beneficiaries of many new ebook downloading and reading technologies, publication software applications, and similar accessories.