Quote from : Genome: the Autobiography of a Species in 23 Chapters Book

Imagine that the genome is a book. There are twenty-three chapters, called CHROMOSOMES. Each chapter contains several thousand stories, called GENES. Each story is made up of paragraphs, called EXTONS, which are interrupted by advertisements called INTRONS. Each paragraph is made up of words, called CODONS. Each word is written in letters called BASES.