Iyini i-Abacus?
Context:I-abacus (ubuningi abaci noma abacuses), ebizwa nangokuthi i-counting frame, iyithuluzi lokubala elisetshenziswe kusukela ezikhathini zasendulo. Yayisetshenziswa eMpumalanga Eseduze yasendulo, eYurophu, eChina naseRussia, kusasele izinkulungwane zeminyaka kwamukelwa uhlelo lwezinombolo lwamaHindu nama-Arabhu. Imvelaphi eqondile ye-abacus ayikaziwa. Iqukethe imigqa yobuhlalu obuhambayo, noma izinto ezifanayo, ezifakwe ocingweni. Zimelela izinombolo. Enye yezinombolo ezimbili iyasungulwa, bese kusetshenziswa ubuhlalu ukuze kwenziwe umsebenzi onjengokungeza, noma ngisho nempande eyisikwele noma eyisikwele.  Emiklamweni yawo yokuqala, imigqa yobuhlalu yayingaxegiselwa endaweni eyisicaba noma igingqike ibe yimigodi. Kamuva lezi zinhlayiya zenziwa zashelela ezindukwini futhi zafakwa ohlakeni, okwenza kube lula ukuzisebenzisa ngokushesha. Ama - abacuses asaqhubeka ekhiqizwa, ngokuvamile njengohlaka olwenziwe ngomhlanga olunamachashazi agudle izintambo. Ezikhathini zasendulo, ikakhulukazi ngaphambi kokwethulwa kwendlela yokubhala, ama-abacus ayewusizo ekubaleni. I - abacus isasetshenziswa ekufundiseni ezinye izingane izisekelo zezibalo, ngokwesibonelo, eRussia.
I-Abacus iyithuluzi lokubala elisebenzisa ubuhlalu obuhambayo ngokuvamile obenziwa ohlakeni lwe-bamboo