Inoculation vs. vaccination Is there any actual difference between inoculation and vaccination or are these terms interchangeable? In case the difference exists, would it be correct to say that inoculation is purposefully infecting a person with a pathogen in a controlled way, even when the person is already infected, to induce immunity while vaccination is administering dead or weakened pathogens to a healthy person as a preventive measure to check future infections? Also, would it be correct to say that vaccination is an advanced form of inoculation?

Both are forms of immunisation.

Inoculation is exactly that. A live organism is introduced in a controlled way, so as to minimise the risk of infection, and is essentially the same process followed by many people in history. It is inherently risky.

Vaccination is introducing a weakened version of the pathogen, so that the immune response is triggered and the body is prepared to fight the actual pathogen if necessary. This was pioneered by Edward Jenner, wherein he noticed that cowpox (related to smallpox) immunised the milkmaids against smallpox.