Digital Marketing
Any marketing that happens through a screen. If a customer could encounter it on a phone, laptop, or smart fridge, it lives here. The umbrella over everything else on this page.
Funnel
The journey from 'never heard of you' to 'just paid you,' imagined as a funnel because you lose people at every stage. The job of marketing is to widen the top and unclog the middle, until a conversion falls out the bottom.
Conversion
The moment someone does the thing you wanted: buys, books, calls, signs up. Everything before it is potential; the conversion is when potential becomes money.
Conversion Rate
Of everyone who had the chance to convert, the percentage who actually did. A shop with 100 visitors and 3 sales converts at 3%. Small changes here move revenue more than most people expect.
CRO (Conversion Rate Optimization)
The unglamorous art of getting more conversions from the traffic you already have. Usually cheaper than buying more traffic, and almost always neglected in favor of buying more traffic.
ROI (Return on Investment)
What you got back versus what you put in. Spend a dollar, make three, that's the number that matters. Every other metric is a supporting actor to this one. See also ROAS.
ROAS (Return on Ad Spend)
ROI's narrower cousin, specific to advertising: revenue earned per dollar of ad spend. A ROAS of 4 means four dollars back for every one spent, before you subtract the cost of making the product.
CPC (Cost Per Click)
What you pay each time someone clicks your ad. In a competitive market this is set by auction, which means your rivals help decide your price whether you like it or not.
CPA / CPL (Cost Per Acquisition / Lead)
What it costs you, all in, to win one customer or one lead. The single most useful number in paid media, because it tells you whether the math works before you scale it up.
CTR (Click-Through Rate)
Of the people who saw your ad or listing, the percentage who clicked. A quick read on whether your message is landing. Low CTR usually means the offer or the wording, not the budget.
Impressions
How many times your thing was shown, whether or not anyone cared. Useful for reach, dangerous as a vanity metric. Impressions don't pay invoices.
KPI (Key Performance Indicator)
The handful of numbers you've agreed actually measure success. The trick is choosing the right ones up front. Start with the wrong definition of success and you've already failed.
Attribution
The detective work of figuring out which marketing touch actually caused the sale. Genuinely hard, often gamed, and the source of most arguments between channels about who deserves credit.
Creative
The actual stuff people see: the words, images, and video. Not a channel, a consumable. Every channel burns through it, and bad creative quietly taxes all of them at once.