Hi Mike,
It really depends what version of the Bible you are reading. If you have one of the One Year Bibles that are sold in stores, then just check to see if it's specifically Chronological or the natural order of the books of the Bible. If you are just using a reading plan, then it depends on the plan you choosed. I hope that helps! Most people are using the non-chronological since that is the one most people are using.
By Chronological, they mean the order of the book readings is based on the date of the events in the Bible. Some events come before or after others in the normal bible order. It's all up to you!
Striving for Christ Everyday,
Paul