The primary aim of this book is to introduce the fundamentals of BASIC, FORTRAN and C++ language using the concepts of Chemistry. Chapters 1-10 give detailed description of BASIC programming language. The various statements like input/output, control statements, arrays, functions and subroutines have been illustrated with various examples from mathematics, science and chemistry. FORTRAN and C++ have been introduced in Chapter11 and 12 respectively. Chapter 11 deals with the principles of FORTRAN programming language. A detailed account of various statements input/output, format, control (if - then - else, go to, do loops etc. has been illustrated by various examples. Chapter 12 deals with the C++ programming and its application to Chemistry. C++ is an extension of C language and is the language of future. In chapters 13 and 14 various softwares used for chemistry have been discussed.