Types of Keywords

A “keyword” in SEO can be a single word or multiple words, as in a “keyword phrase.” There is really no limit to the number of words in a keyword phrase, and over the years people have learned to use an increased number of descriptive search terms in order to
obtain more specific results.
The term “long-tail keywords” is used to distinguish a group of less-searched keywords, which are typically four to seven words or longer. Shorter, more often searched keywords, one to three words in length, are called “short-tail keywords.” You can see from the chart below that shorter keywords are more popular
and searched for more often and the longer keyword phrases are less popular. However, those who use long-tail keywords when searching purchase more often, so long-tail SEO work is very important.

As an example, let's use the product “digital camera.” Some short-tail keyword examples for a digital camera are “digital SLR camera,” “best digital camera,” and “compact digital camera.” Long-tail keyword examples would be “SLR digital camera reviews,” “7 megapixel SLR digital camera,” and “compact professional
SLR digital camera.”