My tenuous, incomplete list [here] of medieval inventions must be updated by those listed in the wonderful book by Chiara Frugoni entitled 'Inventions of the Middles Ages' [2001]. The author has gone directly to medieval source documents and extracted the following creations in the time-frame 500 AD-1500 AD, including:
-Buttons
-Books
-Book distribution/selling
-Book printing
-Guns and gunpowder [usage in war]
-Trousers
-Shoes
-Anaesthetics
-Watermarks
-Manufacturing of paper [the industrialization paper manufacture]
-Movable type and printing presses
-Polyphony in music
-Musical notation
-3 dimensional painting [see Giotto 14th c.]
-Industrialization of art production
-Use of oil-based water colours in art
-Forks
-Private Banks
-Public Banks
-Pasta – all main modern varieties
-Ice Cream
-Playing cards
-Tarot cards
-Ballroom dancing
-Chess [our modern version]
-Domestication of cats
-Glazed windows for common housing
-Ending of Slavery
Some others which should be added to the main extant list:
-Chivalry [code of conduct, fair-play, not the romance]
-Skis
-Ice Skates
-Violin
-Piano
-Most brass and wind instruments
-Romance languages
-English and High German
-Church Slavonic and then Russian
-Large Domes [Haggia Sophia, Brunelleschi's in Florence]
-Study of Political Science
-Church spires [a notable architectural feat]
-Public parks [formal 'common land' never existed before 800 AD]
-Public houses [cheap food, fare for the working class]
-Guilds [a type of union, focused on quality, adequate pricing, skills]
-Church Law [a great improvement over the Pagan and Roman]
-Wheel brakes and proper axles
-Better built roads [Roman roads were narrow, crudely built]
-Rejection of much of naturalist Aristotelian theory which was wrong [abiogenesis etc.]
-Laws of motion and velocity
This partial list is of itself, quite an impressive one.
Some big brains full of historical revisionist nonsense, will wail that Moslems, space-men, the Chinese, the Mayans, or the green-monster cult invented such-and-such. Apocrypha. The Medieval period either independently formed or improved a notably long list of appliances which benefited society at large. A few such as the wheelbarrow were known to the Greeks but discarded [a slave society does not need technology]. It was only in Christian Europe that about 10.000 wind mills were deployed by 1350 AD, grinding and pumping and improving life. Jews, Christians and Greeks had built cruder windmill models in Moslem lands post the irruption of the Jihad, but Moslem culture had little use for such trifles. The same is true of iron smelting, paper and glass production, horse-shoes and horse-collar manufacture, amongst a long list which can be deposited. The Europeans either created or fabricated processes and ideas. No other culture can claim this.