Keywords are ideas and topics that define what your content is about. In terms of SEO, they're the words and phrases that searchers enter into search engines, also called "search queries." If you boil everything on your page — all the images, video, copy, etc. — down to simple words and phrases, those are your primary keywords.
As a website owner and content creator, you want the keywords on your page to be relevant to what people are searching for so they have a better chance of finding your content among the results.
Keywords are important because they are the linchpin between what people are searching for and the content you are providing to fill that need. Your goal in ranking on search engines is to drive organic traffic to your site from the search engine result pages (SERPs), and the keywords you choose to target (meaning, among other things, the ones you choose to include in your content) will determine what kind of traffic you get. If you own a golf shop, for example, you might want to rank for "new clubs" — but if you're not careful, you might end up attracting traffic that's interested in finding a new place to dance after dark.
Keywords are as much about your audience as they are about your content, because you might describe what you offer in a slightly different way than some people ask for it. To create content that ranks well organically and drives visitors to your site, you need to understand the needs of those visitors — the language they use and the type of content they seek. You can do this by talking to your customers, frequenting forums and community groups, and doing your own keyword research with a tool like Keyword Explorer.
Keywords can be broad and far-reaching (these are usually called "head keywords"), or they can be a more specific combination of several terms — these are often called "long-tail keywords."
Singular keywords might appear to be your ultimate goal as they often have temptingly high search volume. However, they usually have extremely tough competition. You may want your boutique clothing store to rank for "clothes," but it's going to be tough to rank above Zappos and Nordstrom.
On top of that strong competition, singular keywords can be infuriatingly vague. If someone is searching for "dog," you don't know if they want a list of dog breeds, information about dog food, a place to buy a dog collar, or just a site with cute photos of dogs.
Long-tail keywords usually have more clearly defined intent. For example, "best organic dog food for a puppy," or "inexpensive dog walkers Seattle." You'll also find that long-tail keywords have less competition, with room for a smaller site to break in and make their mark on the SERPs.
Learn more in our guide to Keyword Research.
It's no good just throwing keywords on your page. Creating compelling content is about providing real value for real people, not just sending hints to our robot friends at Google.
There are some basic keyword usage rules you should follow to get started. Unique keywords should be employed on each page of your site in the areas that bots and humans normally look to reassure them that you have what they're after. This includes both the title tag and the body of your content, which leads to an important point: the pitfalls of clickbait. You may believe you're enticing more clicks by offering tantalizingly vague titles for your content, but by disguising what the page is actually about, you're opting out of some of the power of keywords.
You can also look at working your primary keyword into your URL, an H1 tag on the page, the meta description, and alt attributes of images on the page; all of these places will help clue search engines in on what your content is really about.
Using your keywords in these areas is the most basic way to target your content to searches. It's not going to immediately shoot you to the top of the results, but it is essential SEO; failing to take these basic steps can keep you from ranking by other means.
While you can often start with a keyword and create a piece of content around that term, sometimes your content already exists, and you need to figure out how to match it to keywords. To do this, create what's known as a "content to keyword map." Creating this map can help you understand the impact of your existing content and identify weak links or gaps that need filling.
As keywords define each page of your site, you can use them to organize your content and formulate a strategy. The most basic way to do this is to start a spreadsheet (your "content to keyword map") and identify your primary keyword for each article. You can then build your sheet to your own requirements, add keyword search volume, organic traffic, page authority and any other metrics that are important to your business.
Ideally, you want each page on your site to target a unique primary keyword. Generally speaking, your homepage will target a very broad industry term and as you create category pages, product pages, and articles, they will drill down into your niche and target more specific needs.