In Britain semolina is traditionally (and sometimes derisorily) associated with baked milk puddings and school dinners, however there are many more exotic ways to use it.
South Indian cuisine sees semolina used for kesari, a softly spiced dessert-cum-sweetmeat cooked with milk, cashews and dried fruit, as well as uppuma, a savoury dish somewhere between a pilaf and polenta, flavoured with spices and served for breakfast or as a snack.
Fine semolina flour used for Moroccan yeasted pancakes called beghrir, eaten with honey for breakfast, as well as griddle-baked scone-like cakes called harcha and a range of dense breads.
Italians use semolina ground from hard durum wheat in the manufacture of gnocchi, and pasta (when it's sprinkled on to prevent sticking). It is also employed to make couscous, soups and dumplings and can be substituted for some of the regular flour in cakes and biscuits to give a crisp, crunchy texture - especially scrumptious with shortbread.
Semolina is milled to various degrees of coarseness. Check to see whether the semolina you are buying is made from soft wheat or hard wheat (the durum variety) - the latter is what you need for gnocchi, pasta and home-made couscous.