Digital marketing comes with a language of its own. SEO, PPC, CPC, CTR, ROAS, CPA… Before long, it can feel like your marketing agency is speaking another language.
You don't need to become a digital marketing expert yourself (that’s the point of working with an agency) . But if you're investing money into campaigns, you do need to understand the overview info, otherwise, it's surprisingly easy to mistake impressive-looking numbers for actual business results.
With that in mind, here’s a helpful glossary of the acronyms you're most likely to hear, and why they matter.
The Digital Marketing Glossary
SEO - Search Engine Optimisation
The process of improving your website and content so it appears more prominently in organic search results, such as Google.
Why it matters: Good SEO can bring relevant visitors to your website without paying for every click. But rankings and traffic alone don't necessarily mean you're generating customers.
PPC - Pay-Per-Click
A form of paid advertising where you pay when someone clicks on your advert. Google Ads is one of the most familiar examples.
Why it matters: PPC can quickly put your business in front of the right people, drive targeted traffic and generate valuable enquiries. But without careful management, budget can be spent on clicks that don’t turn into customers.
Impressions
The number of times an ad or piece of content is displayed to someone. For example, if your ad is shown 10,000 times, it’s generated 10,000 impressions. HOWEVER, one person can generate multiple impressions.
Why it matters: It helps measure reach and visibility as impressions demonstrate how often your brand or ad is being seen. High impressions can indicate that your campaign is getting your brand in front of a large audience.
It’s also helpful in providing context for other metrics (impressions are used to calculate CTR and CPM.)
Remember: Impressions don’t mean people have engaged – an ad can generate thousands of impressions but very few clicks or conversions.
CPC - Cost Per Click
How much you pay, on average, for each click on an paid advert (Google Ads, for example)
Example: Spend £500 and receive 250 clicks = £2 CPC.
Why it matters: It helps understand campaign efficiency and manage your budget – a lower CPC generally means you’re getting more traffic for your budget and if you know your CPC you can estimate how many clicks you can afford.
Be aware: the cheapest CPC isn’t necessarily the best campaign: you ultimately want to understand what those clicks do (e.g. whether they generate leads, sales or revenue)
CTR - Click-Through Rate
The percentage of people who see an advert/link and click it.
Example: 1,000 impressions and 50 clicks = 5% CTR.
CTR can be useful for understanding how compelling an advert or search result is, but a high CTR isn't automatically a sign of a successful campaign. You ultimately need to know what happens after the click. If lots of people are clicking your ad, but then not completing the action you’d like them to take (form fill, for example) then the CTR can help show a disconnect between what the ad is promoting, and what your website is promoting.
CVR - Conversion Rate
The percentage of visitors who complete a desired action such as purchasing, booking a call or submitting an enquiry.
If 1,000 people visit your landing page and 50 submit an enquiry, your conversion rate is 5%.
CPL - Cost Per Lead
Specifically measuring the cost of generating a lead.
For example, if you spend £1000 and generate 50 genuine enquiries, your CPL is £20.
The important word is genuine. Thirty irrelevant form submissions aren't necessarily worth more than five highly qualified enquiries.
CPA - Cost Per Acquisition
Similar to CPL, but this measures how much it costs to generate a desired acquisition, such as a customer or the action you wanted.
Example: £1,000 campaign spend generating 10 customers = £100 CPA.
Why it matters: This is generally much more meaningful to a business than simply reporting clicks or impressions.
ROAS - Return on Ad Spend
Measures revenue generated for every pound spent on advertising. Example: Spend £1,000 and generate £4,000 in attributed revenue = 4:1 ROAS.
Why it matters: It helps answer one of the most important questions in digital marketing – it tells you whether your campaigns made money, and what money you got back for that spend.
It sounds wonderfully simple, but attribution, margins, refunds and repeat purchases can all affect how meaningful that number actually is.
ROI - Return on Investment
A broader measure of whether an investment generated a worthwhile return.
Unlike ROAS, ROI can take the wider costs of a campaign or business activity into account.
Why it’s important: For a business, £10,000 in revenue isn't necessarily £10,000 in profit. That's why ROAS and ROI shouldn't be treated as interchangeable.
LTV - Lifetime Value
An estimate of how much revenue or profit a customer generates over their relationship with your business.
This can dramatically change how you view acquisition costs. A customer who initially spends £100 but goes on to spend £2,000 over several years is very different from a one-off £100 customer.
GA4 - Google Analytics 4
Google's analytics platform for measuring activity and behaviour across websites and apps.
GA4 can provide valuable information about where users come from, what they do and what conversions occur.
But remember: analytics data is only as useful as the tracking and interpretation behind it. It can be easy to misinterpret GA4 data.
For example, you might assume that Organic search is your best marketing channel because it sends the most traffic
What you see:
SEO generates 10,000 users, while paid search generates 5,000.
What you might assume:
SEO is twice as successful.
What might actually be happening:
Paid search could generate significantly more high-value leads or customers despite bringing fewer visitors. E.g.
SEO: 10,000 visitors → 100 customers
PPC: 5,000 visitors → 200 customers
Traffic volume alone doesn't tell you which channel is producing more business!
Why You Don't Need to Run Your Own Campaigns
Knowing what these acronyms mean doesn't mean you should be managing your own Google Ads account at lunchtime.
Digital advertising is deceptively easy to start and considerably harder to manage well.
There are hundreds of decisions involved in a campaign: targeting, bidding, creative, keywords, audiences, landing pages, budgets, tracking, attribution, testing and optimisation.
If you don’t get those decisions right, you can end up paying for poorly targeted audiences, clicks from people who were never going to buy, traffic that doesn’t convert and campaigns that look busy but don’t actually generate any meaningful revenue.
And that's before you consider the technical side of conversion tracking and attribution.
This is where the experienced specialists come in. Their job isn't simply to spend your advertising budget. It's to understand the commercial objective, build the right measurement framework, continually test and optimise campaigns, pull the right levers at the right time and turn meaningful data into decisions.
Don't Let Vanity Metrics Fool You
Perhaps one of the most important reasons to understand the terminology used in digital marketing is so you can ask the right questions of your agency.
An agency might tell you: "Your campaign generated 250,000 impressions and 15,000 clicks!"
That sounds impressive. But your next questions should be:
How many leads did that generate?
How many were qualified?
How many became customers?
What did each customer cost us?
How much revenue did we generate?
And, ultimately, was it profitable?
This is the difference between marketing activity and marketing performance.
Impressions, reach, clicks and engagement can all be useful diagnostic metrics. They're just not necessarily the metrics that pay your bills.
Let the Experts Do the Driving, But Know Where You're Going
The best relationship with a marketing agency isn't one where you need to understand every setting inside Google Ads. It's the one where you understand enough to hold the agency accountable and are able to understand what they're measuring, and why they're measuring it. You know what success looks like and need to understand how their work connects to your actual business objectives.
Never be afraid to ask your agency what all the acronyms mean, several times over if need be. A good agency will always happily explain and will relate it in terms of what they mean in the context of your business.
