Savoiarde

Ladyfingers are said to have originated in the 14th century at the court of the County of Savoy, and were created to mark the occasion of a visit by the King of France. They were particularly appreciated by the younger members of the court and offered to visitors as an example of the local cuisine.

Like other sponge cakes, ladyfingers traditionally contain no chemical leavening agent, and rely on air incorporated into the eggs for their "sponge" texture. Some brands, however, contain ammonium bicarbonate. The egg whites and egg yolks mixed with sugar are typically beaten separately and folded together with flour. They contain more flour than the typical sponge cake. The mixture is piped through a pastry bag in short lines onto sheets, giving the biscuits their notable shape.
Before baking, powdered sugar is usually sifted over the top to give a soft crust. The finished ladyfingers are usually layered into a dessert such as tiramisu or trifle.

They have gained many regional names:

In Argentina: vainillas
In Australia: sponge fingers
In Austria: Biskotte
In Bosnia, Croatia, and Serbia: piškote/piškoti, пишкоте/пишкоти
In Brazil: biscoito champagne (champagne biscuits)
In Bulgaria: bishkoti (бишкоти)
In Canada: ladyfingers
In Chile: galletas de champaña (champagne biscuits)
In China: shǒuzhǐ bǐnggān (手指饼干, finger biscuits)
In Colombia: lenguas (tongues, after their form)
In Cuba: bizcocho
In the Czech Republic: dlouhé piškoty (long sponge biscuits) or cukrářské piškoty (confectioner's biscuits)
In El Salvador: suspiros
In Finland: tiramisukeksit (tiramisù biscuits), savoiardikeksit (savoiardi biscuits), and sokerikakkukeksit (sugar cake biscuits)
In France: boudoirs or biscuits à la cuillère (spoon biscuits) or biscuits champagne
In Germany: Löffelbiskuits (spoon biscuits)
In Greece: savouayiár (σαβουαγιάρ, a French adaptation of the Italian name)
In Guatemala: chiquiadores
In Hungary: babapiskóta (baby sponge cake)
In Indonesia: kue lidah kucing (cat's tongue biscuits)
In Iran: latifeh (لطیفه)
In Israel: biskot (בישקוט)
In Italy: savoiardi
In North Macedonia: biskviti (бисквити)
In Mexico: soletas (little soles)
In Flanders and the Netherlands: lange vingers (long fingers)
In Pakistan: bistiks (بسٹیکس)
In the Philippines: broas or broa (Spanish for some more nutritive types of bread, sometimes misspelled as brojas); variants include camachile and lengua de gato
In Poland: kocie języczki (cats' little tongues) or biszkopty (sponge cakes/biscuits)
In Portugal: biscoitos de champanhe (champagne biscuits) or palitos la reine
In Romania: pișcoturi
In Russia: дамские пальчики (lady fingers) or кошачьи язычки (Cat tongue cookies)
In Slovakia: cukrárske piškóty (Konditor's biscuits)
In Slovenia: bebi piškoti (baby…