This is Part-1 of the two part series on Alkyl Halides. In IIT JEE, UPSEE, WBJEE and various other engineering entrance examinations, the chapter Alkyl Halides plays an important role. About 2-5 questions are being asked from this chapter. This article talks about important concept, formulae and previous year questions related to Alkyl Halides. The concept given in this article is in concise form and can be used for revision before the examination.