What is the difference between Karma and Sanskara
Saṅkhāra refer to all conditioned phenomena. That means everything else apart from Nibbana. Karma refers to volitional acts which is only a subset of Saṅkhāra. All Saṅkhāras come under the first noble truth, i.e. Dukkha. All Saṅkhāras are impermanent. All Saṅkhāras are non-self.