HIV and AIDS

It's important to know what the abbreviations HIV and AIDS represent:

Human (people like us)
Immuno (ability to shake off infectious disease) deficiency (lack of)
Virus (parasites that reproduce within a body)

and

Acquired (a condition a person is not born with)
Immune (ability to shake off infectious disease)
Deficiency (lack of)
Syndrome (collective symptoms that characterize a disease)

The HIV virus attacks the immune system leaving the body vulnerable to chronic infections and opportunistic diseases. People become sick when the HIV virus compromises their immune system, but they die from other diseases that attack the body when its immune system is weak.