1) Head queries are the most frequent. Usually 
consist of 2 words. Head queries are used by trusted respected and the 
most popular resources and market leaders. It's quite difficult and has 
no reason to begin website optimization
 with this type of queries. Popular 2 words query will never bring a new
 website to the top. That's why second type of keywords is in field of 
interest.
2) Tail queries usually consist of 3 
and more words or even can be a phrase. This type of keyword is 
characterized by low frequency of queries per month, but can be 
effective for optimization at the beginning. Long-tail keyword allows to
 appear in the top of search quite fast. Moreover, long-tail keyword is 
the way of fast optimization of blogs and informative sites.
How to select right keywords?
The main problem is to choose right keyword. Success 
of site promotion primary depends on solving this problem. Along with 
their main goal, keywords should bring traffic and increase conversion.
First,
 there are a lot of tools such as Semrush, Word stream, Word Tracker 
that allow to suggest possible keyword options and analyze competitors 
keyword. But the best tactic is to come into your potential client world
 and imagine what queries he uses. The most valuable factor for 
selecting keywords is human element. So suggested queries should be as 
natural as possible. List of 20 the most common queries is enough for 
initial analyze. Initial analyze can be done manually without keyword 
checkers. Just put keyword in search field and find out variations and 
main competitors. Manual analyze allows to estimate situation better. 
Tools are needed for comprehensive keyword investigation.
✔ names of elements/parts/ingredients, if it's possible
✔ detailing solutions, for instance, for SEO service it can be "keyword optimization", "link building", "Internet marketing" and so on.
✔ characteristic of product or service, for example, "High Quality Backlinks"or "effective SEO".
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