Google first identifies keywords in your page titles and block titles, and then in the text of your website.
It is important to understand that google does not only check for keywords that can be placed in the metadata of your pages.
Choosing the right words and expressions in all your titles and text helps Google to reference what your website is about and at the same time improves the way your readers browse and understand the content of your pages.
For more information on this central topic, check the Mini Guide "Choosing Words and Expressions” under "Website Creation Tips”.