introductory

introductory /ˌɪntrəˈdʌktəri/ adjective
introductory
/ˌɪntrəˈdʌktəri/
adjective
Britannica Dictionary definition of INTRODUCTORY
1 
: providing information about someone who is about to speak, perform, etc., or something that is about to begin
2 
: providing basic information about a subject
3 
: intended to attract customers when a new product, service, etc., is introduced