Subscriptions are on the mind for every publisher as Facebook and Google continue to cannibalize ad dollars. But while a lot of media companies aren’t new to the concept (hi print), the industry is very early in exploring the different subscription frameworks in a digital world. That will change.

So let’s start with the basics. What is a subscription? At theSkimm, we define a subscription product as:

• Habitual: It’s part of someone’s routine. They “need” it.
• Recurring: It’s delivered on a regular basis. The user knows what to expect and when to expect it.
• Consistent value proposition: Each element and feature aligns with a centralized value statement. A user should be able to clearly say “I find value in this product because I get X every Y.”

Ultimately, a subscription product is something that hits all the points above. Some may be free, some may be premium. At theSkimm, we think of all of our products as subscription — all users are subscribing to a point of view or a value proposition, even if they aren’t paying. Our newsletter is a subscription product — our audience reads it every day in their morning routine to understand what’s happening in the world. Our calendar is a premium subscription — our audience pays to know what’s coming up in the news and zeitgeist every day.

As media moves into uncharted territory, we’ll start to learn lessons from other industries. So let’s break a few down.

1. Volume: This is purely transacting on amount of content. It’s the same product and content, but users pay for more. This is the traditional publisher route — The New York Times, The Washington Post, etc. are all heavily based on volume.

2. Content A vs. Content B: This is transacting on an entirely different type of content that is considered to be “premium.” Some examples are YouTube Red or ESPN Insider — the core product is free, but users pay to unlock premium, differentiated content.

3. Features: Users pay to have a better experience or additional features within the same product. This is where most non-media companies are operating: Amazon and two-day shipping, Spotify and offline listening, dating apps and unlimited messaging, and many many more. With all these examples, the core experience is the same, and users are paying to unlock a valuable “must-have” feature. The most common route here for media companies is paying for no ads, but it’ll be interesting to see where else they can play in this space that’s traditionally dominated by tech companies.

4. All or nothing: Pretty simple. Pay or get nothing. Most video streaming services operate here — Netflix, Hulu, etc. It’s risky but can work if you have obvious, upfront value.

5. Superfan: Users pay to get special access to things like events, swag, and behind-the scenes looks, generally transacting on brand loyalty and affinity. We’re seeing more publishers try this route, often as “memberships.”

This is not an exhaustive list by any means, and we’re starting to see a lot of companies offer a mix-and-match version of these different models. It’s an exciting time for publishers to rethink their entire value proposition and how that can fit into a subscription model.