This article dwells upon the basic unit of cognitive linguistics, which is a concept. Firstly, we provide an overview of major scientific works written by foreign linguists who pay attention to special aspects and lines of research. Secondly, we analyse conclusions on modern problems in linguistics that are drawn in cognitological studies conducted since the end of the 20th century. We also touch upon the course and practice of cognitive linguistics while considering the connection between cognition and language. In order to study a concept, which is a linguo-philosophical unit of linguistics, we examine the associative and semantic field of the concept "woman" in the Kazakh and English cultures. The linguo-philosophical analysis of the macro concept "blue" and its associative and semantic field in the English and Kazakh languages show that its cultural and personal meaning greatly differ. We prove that conceptual borders of any language display purview, knowledge, feelings, world outlook and life position of the respective ethnos and its distinctive members.