A Bible reader locates a verse by finding the book, then finding the chapter, and finally locating the number that the verse is associated with. Bible verses are expressed in numbers, or occasionally with Roman numerals.
For example, locating John 3:16 requires the reader to first find the book of John in the Bible. This is possible by locating the Bible's table of contents, usually found in the Bible's first pages. The table shows on what page number the first chapter of John lies. Once the reader turns to the first chapter of John, he has to locate chapter 3. Chapter numbers are usually in larger type than the main text. When the reader locates chapter 3, he then has to locate verse number 16. Verse numbers are the same size as the main text, but usually in a bolder type.
References to the Bible sometimes do not refer to just one full verse. For example, a reader might find a reference to John 3:16-21; this requires him to begin reading at the number 16 and end once he reaches number 22. Another format of Bible reference is John 3:16, 22. This means that the reader first reads verse 16 and then skips to verse 22. Another type of reference is John 3:16a. When "a" is used, it means the reader only needs to read the first part of the verse, while a "b" directs the reader to the second part of the verse.