it's a joke

The phrase "it's a joke" is often used to lighten a situation as a defense mechanism. Saying "it's only a joke" is often used when the person has not understood or got offended. Reasons may include: 1. The person was genuinely joking and did not mean to cause confusion or offense 2. The person is backing down after upsetting someone 3. The other person fails to see the point, and is reassured that it's not serious