contrast, refers to "the degree to which a person believes that using a particular system would be free of effort" are
two critical factors of adoption of a new technology by users.
This model integrates perceived usefulness, perceived ease of use, attitude toward the action, intention and actual
use as the original variables of the model with the external variables. It provides an informative representation of
the mechanisms by which design choices influence user acceptance, and should therefore be helpful in applied
contexts for forecasting and evaluating user acceptance of information technology (F. D. Davis et al., 1989).