According to WebMD, aspirin is an nonsteroidal anti-inflammatory drug, which means it is anti-inflammatory and acts as a blood thinner, while paracetamol, known as acetominophen or Tylenol in the United States, is not. Both are pain relievers.
Both drugs also reduce mild fevers. Aspirin is sometimes taken on a daily basis as a blood thinner to help prevent blood clots; usually, patients take a lower dose than is normally used for pain relief, according to WebMD. Patients should only take it as a blood thinner under the direction of a doctor. Paracetamol cannot be taken for this purpose and is not recommended for daily use.