The aim of this book is to eliminate the need of standard books for competitive exams as the time is limited in any exam and in that limited time you have to become proficient in different subjects. Some of the features of this book are topic-wise solved examples and topic wise practice problems as well as level wise exercises at the end of chapter. The most noticeable thing is that we have also highlighted important points that one has to remember in every topic so that subject never feels too bulky.