Online advertising guides

Online advertising is the business of putting a message in front of somebody else's audience, and paying for the privilege. That much has not changed since the first newspaper sold a column inch. What changed is the machinery in between: an advert on a modern website is usually sold by auction, in the moment the page loads, to a buyer neither the reader nor the site owner has ever heard of, at a price determined by a system neither of them can see.

That machinery is not a scandal. It is a reasonable answer to a genuinely hard problem — how to sell one impression, once, at the best available price — and it works well for the very large sites and the very large advertisers it was designed around. It works considerably less well for everyone else. A site with a few thousand engaged readers is often rejected outright, or paid so little that the banner costs more in goodwill than it earns. A business with a few hundred pounds a month is bidding against national advertisers with better data and more room to be wrong.

These guides are written for the everyone else. They explain how the various pieces of online advertising work — how ads are priced, what happens inside an ad request, what the different kinds of platform actually do — in plain terms, without assuming you have bought advertising before. Where a comparison is useful, the guide makes one honestly, including the parts where the alternative is genuinely better.

What the guides cover

The first five explain the subject. Paid ads is about what you are actually buying and who carries the risk under each pricing model. Internet advertising follows a single ad request from the page to the payment, which is the fastest way to understand where the money goes and why consent banners exist. Ads for small business is about spending a small budget well, and measuring it without tracking anyone. Local ads covers the case where the customer has to be able to walk in, which changes what reach is even worth. Online ads platforms sets out the four kinds and the seven questions that separate them.

The last three are comparisons with the largest self-serve platforms, because those are what most people mean when they say they are "doing some advertising". They are written to be fair: these systems do things a direct ad space cannot, and the guides say so.

The argument running through all of them

If you own a website, you own the only part of this that is genuinely scarce: an audience that chose to be there. Everything else in the chain — the exchange, the bidder, the measurement layer — is infrastructure built on top of that audience, and it is infrastructure you can choose how much of to use.

Owning your advertising pipeline means four specific things, and each is worth defending: you set the price on your own inventory, you decide who is allowed to advertise beside your writing, you know what each payment was before anything was deducted from it, and the money arrives in your own account. None of those requires leaving the large platforms behind. They are simply the things a website owner should not hand over by default, and for most of the last decade the only practical way to keep them was to sell space by hand.

Perch exists to make that practical again: a sized slot on your page at a daily rate you set, an advertiser you approve, one line of code, and a 25% service fee stated on screen before you agree to anything. If you would rather see the mechanics than the argument, the help centre is the short version and you can create an ad space in about a minute.