The present book is the first Issue of a Series explaining various mathematical terms and concepts. It introduces the topics, definitions, main results and theorems avoiding proofs of the results. It may serve as a reference book. The first Issue consists of topics in Mathematical Analysis. The remaining ones covering topics of other mathematical disciplines will follow in the sequel. The contents are divided into Sections - numbered chapter wise. The discussion within the Sections is presented in the form of Definitions, Theorems, Notes and Examples. These subtitles within the Sections are numbered in decimal pattern. For instance, the equation number (c.s.e) refers to the eth equation in the sth section of Chapter c. When the number c coincides with the chapter at hand, it is dropped. Adequate references to the previously quoted results are made in the text avoiding their unnecessary repetition. For brevity, some set-theoretic notations and symbols are frequently used, e.g. the symbol ? means implies. The logarithm of a number to the exponential base e is denoted by ln. All the Latin mathematical symbols are normally italicized, while their Greek counterparts are in normal fonts.