The Reply Two Email Marketing Wiki
Everything you need to know about email marketing
Trying to decode some corporate email jargon? The Reply Two email marketing wiki spells things out in language we can all understand. Each definition has a handy prompt you can copy and paste too.
Email Service Provider
An Email Service Provider (ESP) is the platform that handles sending, tracking, and managing your newsletter. It's the engine that powers your entire email operation, from signup forms to sending campaigns to measuring results. ESPs like beehiiv, Substack, Mailchimp, Kit, Brevo, and others each offer different feature sets tailored to different creator needs.
Read more on Email Service ProviderOpen Rate
Open Rate refers to that percentage your email service provider brags about when people supposedly "open" your emails. It's tracked by a tiny invisible pixel that loads when someone views your message, or when their device pretends to.
Read more on Open RateOverall ROI
Overall ROI for email newsletters is the brutal reality check of what you're putting in versus getting out. It tallies everything from your precious time to your tech stack costs against what's actually hitting your bank account from sponsorships, subscriptions, and other revenue streams.
Read more on Overall ROIPodcasting
Podcasting is creating episodic audio content that lets newsletter writers invade subscribers' earbuds when eyeballs are busy elsewhere. It's your written insights converted to sound, perfect for commutes, workouts, or pretending to listen to your boss while actually learning something useful. A Podcast is the downloadable audio show itself. Your newsletter's cool cousin who gets invited to all the multitasking parties. Episodes live on subscribers' phones, ready to feed their brains whenever reading isn't an option but their curiosity remains.
Read more on PodcastingPublisher
A publisher in email newsletters is the entity that creates and sends the whole enchilada to subscribers. It could be a solo writer, a small team, or a media company. They're the ones making content decisions, building the audience relationship, and figuring out how to turn all those clicks into actual money.
Read more on PublisherRecurring Affiliate Program
A recurring affiliate program is a partnership where you earn commissions repeatedly for as long as your referred customers remain active with the service. Unlike traditional one-time programs, recurring affiliate deals keep paying you month after month or year after year from a single successful referral. Think of it as owning a rental property that generates income without additional work versus a house-flipping deal that pays once then disappears.
Read more on Recurring Affiliate ProgramRoot Domain
The root domain is the main web address of your site or email sending infrastructure, without any subdomains or paths. It's the bare-bones URL that forms the foundation of your digital presence. E.g., yourbrand.com is the root domain of newsletter.yourbrand.com
Read more on Root DomainShared IP
Shared IP means your newsletter sends from an IP address used by multiple senders through your email service provider. It's like sharing an apartment building's mailing address with other tenants. Your reputation depends partly on how well your neighbors behave with their sending practices.
Read more on Shared IPSplit Testing
Split testing (also known as A/B testing) is dividing your subscriber list to send different newsletter versions and see which performs better. You test one element at a time by pitting your current best version, the "control" or "champion," against a new version, the "challenger." You can test anything from subject lines to layout to CTAs, measuring success through opens, clicks, or conversions to make data-driven decisions.
Read more on Split Testing