There are many commonly used abbreviations in discussing Health IT. I thought it might be helpful to list some here:
AHIC American Health Information Community
AHIMA American Health Information Management Association
AHRQ Agency for Healthcare Research and Quality
ANSI American National Standards Institute
CCHIT Certification Commission for Healthcare Information Technology
CDS Clinical Decision Support
CHC Community Health Centers
CMS Centers for Medicare and Medicaid Services
CONNECT NHIN gateway
CPOE Computerized Physician Order Entry
EHR Electronic Health Record
EMR Electronic Medical Record
FHA Federal Health Architecture
HHS Department of Health & Human Services
HIE Health Information Exchange
HIMSS Healthcare Information Management Systems Society
HIPAA Health Insurance Portability and Accountability Act
HIT Health Information Technology
HITSP Health Information Technology Standards Panel
HL7 Health Level 7
HRSA Health Resources and Services Administration
ICD International Statistical Classification of Diseases and Related Health Problems
JCAHO Joint Commission on Accreditation of Healthcare Organizations
NCVHS National Committee on Vital and Health Statistics
NHIN Nationwide Health Information Network
NIH National Institutes of Health
NLM National Library of Medicine
ONC Office of the National Coordinator (usual abbreviation for ONCHIT)
ONCHIT Office of the National Coordinator for Health Information Technology
PHR Personal Health Record
PQRI Physican Quality Reporting Initiative
RHIO Regional Health Information Network
SLHIE State Level Health Information Exchange Consensus Project
SNOMED Systematized Nomenclature of Medicine
VHA Veterans Health Administration
VistA Veterans Health Information Systems and Technology Architecture
I particularly would like to point out the differences between EMR, EHR and PHR. These terms tend to be used interchangeably, but they actually refer to different things. In fact the definition of EHR depends a lot on what the definiton of "meaningful use" is. You could define an EMR as just the physician interface and EHR including both a physician and patient interface (with some interoperability between systems). PHR is still an ill-defined concept that has been slowly developing over many years. Certainly PHR is a computerized application that stores an individual's personal health information. The key difference being that a PHR is typically a health record that is created, controlled and maintained by an individual patient, while the EMR is created, controlled and maintained by the provider. Hopefully one day we will have an intersection at truly meaningful EHR.