Here are some definitions of the 3 main kinds of searches that a user might do. They are important as they hold the intent of the users and if you believe this, might influence the response and what is relevant results from a search engine!.
A navigational search is a specified search and is successful if your product is a specific brand name. Searches like ‘Tesco’ or ‘Diesel Jeans’ means that that those websites optimising for that brand would appear above all the others so for smaller companies it is not necessarily the best way to optimise your site as it is highly competitive against other more commercial companies.
If you are selling or are the owner of a brand, people are effectively looking for you, but may end up on a site that is optimised for your product. Affiliates and domain squatters can do very well here. This can also apply to events, generics, news items or popular culture.
This is a better way for small businesses to optimise their site. They can aim to rank highly for a simple phrase and make it more plausible. A couple of words creating a generic phrase are far more successful than depending on brand names to get traffic to a site. Phrases such as “tyres Chiswick” can be far more effective for businesses rather than a brand of tyres. The risk of using a brand is that it is likely to be supplied by big chain stores nationwide that already have a good amount of traffic to their site.
This could be a bit of a leveler on the internet. The internet was meant to allow small businesses to compete with anyone, anywhere. In practice this is not the case, but especially on local search or map searches smaller players can win and from my hunt for new car tyres yesterday, small businesses who register for local business on Google appeared on a map in the no1 slot and did very well in the map channel.
These searches are far more specific and contain a lot of words that identify what a consumer wants in finer detail. For example “cheap tyres Hammersmith London (& maybe brand).” All of the sites that contain these words will come up in the search engine results and your company may be there but the amount of people using this method of searching are fewer than the others.
Fewer in quantity, but fairly precise. The longest keyword phrase I have seen that has come to a site I have worked on was 18 words in length. Funnily enough, 100% conversion rate to transaction. Now the quantity of unique long tail terms can be big, but may only happen once or twice per year. But you might be lucky and if you are in the right business the total volume might be huge!
Keywords definitely vary by industry and country. And depending on your industry, and your type of product, the age/demographics or sophistication levels of your customers and potential customers will depend on your keyword usage.
You will need to understand your customers (marketing 101 don’t forget all that you know from the old world order) and enough you optimise your business and your site to make sure you are found ahead of the competition.
Look at your keyword reports, ask you customers virtually or face-to-face if you can how they found you, how they want to find your service or product.
This is part science, part human skills and a bit of luck. If you kind of understand your customer you have a chance to satisfy their needs.