As soon as you get your first medical billing and coding job — and probably even before that — you’ll start hearing about something called ICD-10, which is the 10th edition of the International Classification of Diseases (hence, the ICD), the common system of codes that classifies every disease or health problem you code.

These diagnosis codes represent a generalized description of the disease or injury that was the catalyst for the patient/physician encounter. As a biller/coder, you use the ICD every day.

ICD codes are also used to classify diseases and other health problems that are recorded on many types of health records, including death certificates, to help provide national mortality and morbidity rates.

The ninth edition of the ICD classification (ICD-9) has been used in the United States since 1979. But ICD-10 is coming, ready or not, and it isn't just an update to the old version. ICD-10 is a completely new edition, with all codes rearranged and placed in different areas.

ICD-9 is the old-school coding classification system, while ICD-10 is the new kid in town, and the differences between the two are fairly significant. For starters, ICD-9 has just over 14,000 diagnosis codes and almost 4,000 procedural codes.

In contrast, ICD-10 contains more than 68,000 diagnosis codes (clinical modification codes) and more than 72,000 procedural codes. Other differences involve how the codes are presented (the number of characters, for example) and how you interpret them (deciphering the characters to know what particular groupings mean).

As of this writing, all healthcare providers are obligated to be ICD-10–ready by October 1, 2014. Because getting everyone the world over on the same page, so to speak, is such a gargantuan job, ICD-10 is being implemented in phases for just about anyone who has anything to do with using it.

The World Health Organization (WHO) uses the data gleaned from your coding to analyze the health of large population groups and monitor diseases and other health problems for all members of the global community. For your purposes, you can think of the ICD codes as the language you speak when coding so that organizations like WHO can do the work of keeping the world healthy.

Changing over to ICD-10 could do you good. Currently, medical billing and coding jobs comprise one-fifth of the healthcare workforce, a number that is expected to grow. Transitioning to ICD-10 is expected to increase the demand for medical coders because it will make the coding and billing process more complicated and time-consuming.