AnswerThePublic shows current trends with a color-gradient wheel of keywords, organized in a formation set from lighter to darker orange dots and divided into modifiers, such as WHAT, ARE, WHY, and so on. You may wonder what the color-gradient dots beside each keyword means.
These orange dots are basically a thermometer for popularity. The dot indicates how popular or how unpopular the keyword is - compared to the other keywords inside that Modifier branch.
It is essential to clarify that popularity does not always equals the highest search volume.
Keywords with a low volume (or no volume) can appear as more popular than higher volume terms. AnswerThePublic collects trends from Google’s AutoComplete data and uses it to generate reports.
i.e. Both Common and Trending keywords are part of AutoComplete data.
Darker Orange = More Popular.
Terms with a dark orange dot will indicate the emerging, most relevant keyword in that branch. While keywords with a lighter orange are less relevant at the moment.
Some more details...
AutoComplete aims to predict which are the most relevant searchers to the keyword you are typing. The predictions are made up of common (likely to be higher volume on average) and trending suggestions (perhaps new search terms with less volume, but they are trending) relevant to the characters that are entered.
If the results were only ordered based on high search volumes, things like brand-new products, models or events relating to a keyword would not appear. i.e., the search volume would be too low vs. other generic terms. So by including trending (popular) keywords, more timely and relevant results can also be shown.
However, we offer CPC and Volume values information beside each keyword. So, you can have a better picture of the keyword's importance to your niche.
You can read more about how AutoComplete works here.