ROAS Return on ad spend
Revenue divided by ad spend (3x means $3 back for every $1 spent).
Why it matters Your headline profitability signal. Know your break-even ROAS before you judge any campaign.
Shared Learnings
Digital Advertising Glossary
The paid-media terms new advertisers actually trip on, in plain English, with the part a dictionary leaves out: why each one matters and how practitioners treat it.
Across Google, Meta, TikTok, Microsoft, Snapchat and Pinterest. Curated by the Shared Learnings team.
CPA Cost per acquisition
Ad spend divided by the number of conversions (a sale, lead or signup).
Why it matters The number to watch for lead gen. Compare it to what a customer is worth, not to zero.
CPC Cost per click
What you pay each time someone clicks your ad.
Why it matters Rises with competition. A high CPC is not bad if those clicks convert.
CPM Cost per mille
Cost per 1,000 impressions.
Why it matters How expensive an audience is to reach. Useful for comparing placements, not for judging results on its own.
CTR Click-through rate
Clicks divided by impressions, as a percentage.
Why it matters A quick read on whether your ad and targeting resonate. Low CTR is usually creative or audience, not budget.
CVR Conversion rate
Conversions divided by clicks or visits, as a percentage.
Why it matters Where most beginners lose money. A great ad with a weak landing page still fails here.
AOV Average order value
Average revenue per order.
Why it matters Sets how much you can afford to pay per sale. Raising AOV loosens every other constraint.
CAC Customer acquisition cost
The total cost to acquire one paying customer.
Why it matters Like CPA but for the whole customer, not a single conversion. Compare it to LTV.
LTV Lifetime value
The total profit a customer brings over their lifetime.
Why it matters If LTV is above CAC you can scale. If not, more spend just loses money faster.
Impressions
The number of times your ad was shown.
Why it matters Volume, not results. Big impressions with no conversions is a targeting or offer problem.
Reach
The number of unique people who saw your ad.
Why it matters Impressions count repeats, reach does not. Watch reach so you do not fatigue the same people.
Frequency
Average times each person saw your ad (impressions divided by reach).
Why it matters Rising frequency with falling results means ad fatigue. Refresh creative or widen the audience.
Learning phase
The period a new campaign gathers data before the platform stabilises delivery (Meta needs roughly 50 conversions a week).
Why it matters Do not judge or edit a campaign mid-learning. Edits reset it and waste spend.
Advantage+ / ASC Advantage+ Shopping Campaigns
Meta's heavily automated campaign type that hands targeting and placement to the algorithm.
Why it matters Often strong for ecommerce with good signal, but the platform pushes it hard. Decide with evidence, not the nudge.
Performance Max PMax
Google's fully automated campaign spanning Search, Display, YouTube and Shopping.
Why it matters Powerful but a black box. Guard your brand search and add exclusions or it can cannibalise cheaper traffic.
Pixel
A snippet on your site that reports visitor actions back to the ad platform.
Why it matters If it is missing or misfiring, the platform optimises blind. Verify it before you spend.
CAPI Conversions API
A server-side way to send conversion data to Meta, alongside or instead of the pixel.
Why it matters Recovers signal lost to ad blockers and iOS. Increasingly needed for accurate optimisation.
Lookalike audience
An audience the platform builds to resemble a source list, such as past buyers.
Why it matters Only as good as the source. A lookalike of 20 random emails is noise.
Custom audience
An audience you define from your own data (site visitors, a customer list, engagers).
Why it matters Your warmest, cheapest-converting targeting. Build these before chasing cold reach.
Retargeting Remarketing
Showing ads to people who already interacted with you.
Why it matters High ROAS but small. Do not mistake retargeting return for new-customer growth.
Prospecting
Advertising to new, cold audiences who do not know you yet.
Why it matters Where real growth comes from, and where CPAs are highest. Budget for it separately.
Top / mid / bottom of funnel ToF / MoF / BoF
The stages from awareness (cold) to consideration to purchase-ready.
Why it matters Match the ask to the stage. A buy-now ad to a cold audience usually flops.
Match types Broad / phrase / exact
Google keyword settings, from loosest (broad) to tightest (exact).
Why it matters Broad match plus automation can burn budget on junk queries. Watch your search terms report.
Negative keywords
Terms you exclude so your ads do not show for them.
Why it matters The cheapest optimisation in search. A good negative list stops silent waste.
Quality Score
Google's 1 to 10 rating of keyword, ad and landing-page relevance.
Why it matters A higher score means lower CPC and better position. Usually a landing-page-relevance fix.
Smart Bidding tCPA / tROAS
Automated bidding that aims for a target cost per conversion or return.
Why it matters Needs conversion data to work. An unrealistic target starves delivery.
CBO Campaign Budget Optimization
A Meta setting that spreads one budget across ad sets automatically.
Why it matters Hands allocation to the algorithm. Good at scale, but it can starve a promising ad set early.
Attribution
The rules that decide which ad gets credit for a conversion.
Why it matters Different windows and models tell different stories. Know yours before comparing platforms.
Conversion window
The time after a click or view within which a conversion is credited.
Why it matters A 7-day window flatters ROAS versus a 1-day window. Compare like with like.
A/B test Split test
Running two variants to see which performs better.
Why it matters Only trust the result if the difference is big and the sample is large enough. Small tests mislead.
UTM parameters
Tags added to a URL so analytics can attribute the visit to a campaign.
Why it matters Get these consistent from day one or your reporting becomes guesswork.
Landing page
The page a visitor arrives on after clicking your ad.
Why it matters Where most ad budgets die. Message match and speed matter more than another targeting tweak.
Hook
The first few seconds or first line of an ad that stops the scroll.
Why it matters On feed platforms the hook decides everything. A weak hook is a wasted impression.
Placement
Where your ad appears: Feed, Stories, Reels, Search, Display and so on.
Why it matters Auto-placements are convenient but can spend on low-quality spots. Review where budget actually went.
Audience Network
Meta's network of third-party apps and sites where your ads can show.
Why it matters Often low-quality traffic for beginners. Check its results before you leave it on.
Bid strategy
How you tell the platform to bid: manual, maximise clicks or conversions, or a target CPA/ROAS.
Why it matters Automated strategies need conversion data. Start simpler if you have none yet.
Impression share
The share of available impressions your ads actually won.
Why it matters A low share can mean budget or bid limits. It tells you how much headroom you have to scale.
Creative
The ad itself: the image, video and copy.
Why it matters The single biggest lever on modern platforms. When results dip, test creative before settings.
Objective Campaign objective
The goal you pick at campaign creation (awareness, traffic, leads, sales).
Why it matters It changes who the platform shows you to. Picking traffic when you want sales optimises for the wrong thing.
Dayparting Ad scheduling
Restricting the times or days your ads run.
Why it matters Rarely worth it early. You need volume before day-of-week patterns are real.