By now, Amazon.com (NASDAQ:AMZN) customers and investors alike are familiar with Prime Day, the company's "Black Friday in July" sale. The yearly event, which concluded its fourth annual sale this past summer, is available only to Prime customers and those on a trial subscription. Each successive event is bigger than the last, and Amazon revealed that the 2018 event was "the biggest global shopping event in Amazon history, beating out the previous years' Black Friday and Cyber Monday."

With success of that magnitude, Amazon tried to invent another shopping event, perhaps in an effect to catch lightning in a bottle once again. In late 2016, Amazon announced the debut of a sale that would focus strictly on digital content across its website. Dubbed Digital Day, the event offers "great end-of-year savings on digital content across Amazon," according to a company press release. After its sophomore effort last year, the sale is back.

Digital Day

Amazon's third annual Digital Day will take place on Friday, Dec. 28, and "[c]ustomers will be able to access thousands of deals across digital content including movies, TV shows, mobile games, apps, eBooks, and more." The focus on digital items shouldn't be a surprise, because all the new devices consumers picked up for Christmas will be in need of content. The company provided a sneak peek at some of the deals that will be available:

Up to 80% off on Marvel graphic novels like Jessica Jones: Blind Spot, Runaways Vol. 1: Pride and Joy, You Are Deadpool, and X-Men: Days of Future Past.

Up to 75% off Kindle's best-selling e-books, including titles such as Manhattan Beach, In the Midst of Winter, My Squirrel Days, Summer I Turned Pretty, Indianapolis, and Great At Work.

Up to 60% off digital magazines such as Vanity Fair, People, Entertainment Weekly, Martha Stewart Living, Better Homes and Gardens, Bon Appetit, Wired, Shape, and Men's Journal.

Savings on hundreds of movies including Incredibles 2, Christopher Robin, The Spy Who Dumped Me, Ant-Man and the Wasp, and Avengers: Infinity War.

Prime members can save 65% off movies like Jurassic World: Fallen Kingdom, Red Sparrow, Sicario: Day of the Soldado, Tomb Raider, and Book Club on Prime Video.

The e-commerce specialist also has savings on popular in-game items, software, e-books, and more. Customers that start new paid subscriptions to streaming services available via Prime Video -- including AMC Premiere, CBS All Access, ESPN+, and Showtime -- will get a $10 Amazon credit.

Amazon said that some deals would be available as early as Dec. 26, with the biggest savings launching at midnight Pacific Standard Time on Dec. 28. You can sign up for notifications at amazon.com/digitalday, or follow #DigitalDay.

Lightning doesn't strike twice, but...

This year's Prime Day in July was a resounding success. Consumers had more than 1 million deals available, and Amazon revealed that it sold more than 100 million products during the 36-hour event, with its Echo Dot smart speakers and Fire Stick TV with Alexa Voice Remote nabbing the title of biggest sellers.

It's unlikely that Amazon's Digital Day event is as popular with customers as Prime Day, and the company doesn't provide the same post-sale coverage, but Digital Day most likely provides a year-end increase in revenue.

The event could also deliver a significant boost to the bottom line. Items like apps, software, mobile games, digital movies and e-books all have one thing in common: They can be downloaded, avoiding the additional cost that comes with shipping physical goods. Thus, they typically come with higher margins.

Digital Day provides one more example of how Amazon capitalizes on consumer behavior. The company will offer up a ton of digital deals in the wake of the holidays, just when many customers will be in search of content for their new electronic devices.