How is monkeypox different from smallpox?

Less fatal. The monkeypox virus is in the same genus as the smallpox virus and the rashes looked similar. Smallpox has been eradicated. Monkeypox is less transmissible between humans than smallpox. The fatality rate is much lower with monkeypox.
Pox viruses. Monkeypox & Smallpox are both Orthopoxviruses. Monkeypox can cause lymph node swelling & is a less severe disease than smallpox. African fatalities from Monkeypox are 1 to 10%. Fatalities from smallpox are 30% & close to 100% wi some subtypes. Smallpox in nature has been eradicated.