Backlink

A backlink is a link on someone else’s website that points to yours. Search engines read it as a signal: another site decided you were worth sending people to, so you are probably worth showing. That is the whole idea. Everything else about links is detail hanging off it, and most of that detail lives inside the link itself rather than in how you got it.

In short

• A backlink is a link to your site from a site you do not own.
• The wording, the placement and the attributes decide what it is worth.
• Buying and selling links both break the rules, and both sides carry risk.
• How links are earned is a separate subject, covered under off-page SEO.

Why a link counts as a vote

Search engines needed a way to separate pages that were genuinely useful from pages that merely existed, and links gave them a rough but workable answer. If many independent sites point at one page, that page is probably worth something. The idea is old. It still holds.

It holds because a link costs the person giving it something. They have to decide you are worth mentioning, then put your name on a page they are responsible for. That small cost is the entire reason it works as a signal. Once links become free to obtain in bulk, they stop meaning anything at all, which is exactly what happened to paid directory listings twenty years ago and what happens to every shortcut sold since.

The parts of a link

A link looks like one thing and is really four, and each part carries information.

• The destination. Which page it points at. A link to a service page and a link to your home page do different work.
• The link text. The visible words, called the anchor text. These describe your page to anybody reading and to anything crawling.
• The attributes. Optional markers attached to the link that tell search engines how to treat it.
• The surroundings. The sentence, the page and the site it sits in, which is what makes a link look natural or arranged.

What the link text does

The visible words are the only part of a link that describes your page in somebody else’s words, which is why they carry weight out of proportion to their size.

There is a trap in them. Wording repeated identically across dozens of sites is the most recognisable footprint of arranged linking there is, and the wording on links you did not place is not yours to decide anyway. How to choose it where you can, and where being deliberate is safe, is on the anchor text entry.

The attributes you will see

Three markers can be attached to a link, and they change what it means to a search engine rather than to a reader.

• nofollow. Asks search engines not to pass ranking value. Since 2020 Google treats it as a hint rather than an instruction, so it may still count for something.
• sponsored. Marks a link that was paid for, in money or in goods. This is what a bought link is supposed to carry.
• ugc. Marks user generated content, such as comments and forum posts.

None of these make a link worthless. A nofollow link from a site your customers actually read still sends real people, and real people were always the point.

What makes one link worth more than another

Beyond the parts, a few things about the page hosting the link decide most of its value.

• Relevance to what you do. A dental supplier linking to a dental clinic makes obvious sense. A car forum linking to the same clinic does not, and the mismatch is visible to anybody looking.
• Where it sits. A link inside the body of a genuine article counts for considerably more than one buried in a footer or a sidebar.
• How much company it keeps. A link on a page carrying three links is worth more than the same link on a page carrying two hundred.
• Whether the page is indexed at all. A link on a page search engines have never stored has not been seen, and does nothing.

Reading your own links

Links never resolve into one clean number, which is the main reason people give up on measuring them and fall back on counting. There are better things to watch.

Search Console lists the sites linking to you, and it is the only list that comes from Google rather than from a tool making an estimate. The number worth tracking there is separate domains rather than total links, because fifty links from one site are closer to one vote than to fifty.

Then look at whether the specific pages you care about are gaining, since a useful link tends to lift one page before it lifts anything else. Watch how many visits arrive through the link itself, because a link that sends real people earns its place whatever it does in search. And notice how long links survive: links on genuine sites tend to stay put, while links from sellers disappear the month the invoice stops.

Why buying them fails mechanically

The argument against bought links is usually moral, and the practical argument is stronger.

A seller has to sell the same placements repeatedly to stay in business, so their pages accumulate links to unrelated businesses in unrelated trades. That pattern is what gets the site identified, and it is not something an individual buyer can avoid by choosing carefully. When the site is discounted, every link on it goes at once, including yours.

The money is also spent on something you do not own. The link exists while the arrangement continues and vanishes afterwards, which makes it a rental rather than an asset. This is why the businesses with genuinely strong link profiles almost never built them this way.

Where links fit next to everything else

Links are one of three things search engines weigh, sitting alongside the content on your pages and whether the site itself works properly. They are also the slowest of the three to move, and the only one that depends on other people agreeing to help you.

That ordering matters when you are deciding where effort should go. A business with thin pages and a site that loads slowly on mobile data does not have a link problem yet, whatever a tool tells it. Fixing the pages is faster, costs less, and is entirely within your control.

How links are actually earned, along with the mentions, listings and reviews that sit beside them, is covered under off-page SEO. The wording you choose for links inside your own site is part of on-page SEO.