The purpose of this book is presentation and explanation (explication) of main catchwords in the branch of temperature measurements and nanomeasurements. At the first place it destined for engineers, lecturers, students, persons who are not acquainted enough with specificity of temperature measurement but are interested in it and study literary sources in this realm. The authors tried to enter maximally on catchwords list the issues which refer directly or indirectly to thermometry as well as to nanothermometry. The latter is the most modern chapter of thermometry and simultaneously of nanometrology.