Ukrainian language (ukrayins’ka mova) is the official language of Ukraine. It is one of the East Slavic languages like Russian and Belorussian. These languages use the Cyrillic alphabeth. Ukrainian language is currently emerging from a long period of decline. But it is mostly prevalent in Western Ukraine (where it undergone some Polish influence).
In Kiev (Kyiv), both languages Ukrainian and Russian are spoken. Actually, this is a notable shift from the recent past when the city was primarily Russian speaking. The shift is caused, largely, by an influx of migrants from the western regions of Ukraine but also by some Kievans’ turning to use the language they speak at home more widely in everyday matters. In northern and central Ukraine, Russian is the language of the urban population, while in rural areas Ukrainian or a mix of Ukrainian and Russian (called “surzhik”) is much more common. This is also true of much of the south and the east. But you can hardly find anybody speaking Ukrainian in Crimea.