COHORT A  Inclusion Criteria:  20-85 years of age Recently completed ultrasonography examination. Recently diagnosed with (or strong clinical suspicion for) primary NAFLD. At least 7 days before but no more than 2 months after the most recent ultrasonography Able and willing to provide blood samples per protocol Able to comprehend and willing to sign and date the written informed consent document(s) and any applicable medical record release documents for the study  Exclusion Criteria:  Alcohol abuse (weekly ethanol consumption: >140 g for men and >70 g for women) in the past year. Personal history of NAFLD (other than most recent diagnosis) Ultrasonography within the previous 9 years (other than most recent diagnosis) A history of fatty liver or other liver diseases such as autoimmune hepatitis and drug-induced liver disease. Have a medical condition which, in the opinion of the investigator, should preclude enrollment into the study. Have participated or be currently participating in a clinical research study in which an experimental medication has been administered during the 60 days up to and including the date of providing informed consent or may be administered through the time of the ultrasonography. If female, known to be pregnant.  COHORT B  Inclusion Criteria:  20-85 years of age Planning to undergo a screening ultrasonography within 2 months after providing signed informed consent Able and willing to provide blood samples per protocol Able to comprehend and willing to sign and date the written informed consent document(s) and any applicable medical record release documents for the study  Exclusion Criteria:  Alcohol abuse (weekly ethanol consumption: >140 g for men and >70 g for women) in the past year. Personal history of NAFLD Ultrasonography within the previous 9 years A history of fatty liver or other liver diseases such as autoimmune hepatitis and drug-induced liver disease. Have a medical condition which, in the opinion of the investigator, should preclude enrollment into the study. Have participated or be currently participating in a clinical research study in which an experimental medication has been administered during the 60 days up to and including the date of providing informed consent or may be administered through the time of the ultrasonography. If female, known to be pregnant.  COHORT C  Inclusion Criteria:  20-85 years of age Recently completed ultrasonography examination. Recently diagnosed with (or strong clinical suspicion for) NASH, an extremely advanced form of non-alcoholic fatty liver disease (NAFLD), defined as hepatic steatosis with inflammation and hepatocyte injury.. At least 7 days before but no more than 2 months after the most recent ultrasonography Able and willing to provide blood samples per protocol Able to comprehend and willing to sign and date the written informed consent document(s) and any applicable medical record release documents for the study  Exclusion Criteria:  Alcohol abuse (weekly ethanol consumption: >140 g for men and >70 g for women) in the past year. Personal history of NAFLD or NASH (other than most recent diagnosis) Ultrasonography within the previous 9 years (other than most recent diagnosis) A history of fatty liver or other liver diseases such as autoimmune hepatitis and drug-induced liver disease. Have a medical condition which, in the opinion of the investigator, should preclude enrollment into the study. Have participated or be currently participating in a clinical research study in which an experimental medication has been administered during the 60 days up to and including the date of providing informed consent or may be administered through the time of the ultrasonography. If female, known to be pregnant.