Oregano and sweet marjoram are closely related perennial, culinary herbs. Both are cultivated for their aromatic leaves used fresh or dried as seasoning in many regional cuisines. They are often used interchangeably.
https://sonomamg.ucanr.edu/Food_Gardening/Feature_Vegetables/Oregano_-_Marjoram/
Parsley, a member of the carrot family (Apiaceae), is a hardy biennial grown as an annual. This versatile herb is used in cooking or as a garnish and may be harvested in Sonoma County year-round. For its continued presence in the garden, set out new plants each year or allow an existing plant to reseed.
https://sonomamg.ucanr.edu/Food_Gardening/Feature_Vegetables/Parsley/