Some common Slavic languages:
A number of Slavic languages, most notably those of the East Slavic branch and some of those of the South Slavic branch, are written in the Cyrillic script. Old Church Slavonic is written in the Glagolitic script, from which the Cyrillic script is probably derived. All the others are written in the Latin script. Notably, one of the major distinctions between Serbian (Serbo-Croatian as spoken in the east---primarily Serbia) and Bosnian and Croatian (Serbo-Croatian as spoken in the west---primarily Croatian in Croatia and Bosnian in most of Bosnia-Hercegovina) is that the first is written in Cyrillic and the last two in Latin.
Slavic languages typically have rather complex case systems compared to many Indo-European languages. Macedonian and Bulgarian, though, have mostly replaced their system of declension with the use of prepositions. Many Slavic languages have a dual number, in addition to singular and plural. Finally, in many Slavic languages verbs come in pairs---a perfective verb, which denotes the completed action, and an imperfective verb, which indicates an incomplete action; that is, such languages are hybrid aspectual languages.
The Slavic languages belong to the satem branch of the Indo-European language family. `Satem', after the Avestan word for `hundred', means that the Proto-Indo-European palatovelar consonant *k' (not labiovelar *kw) tends to become a sibilant (s or a similar sound). The other members of the palatovelar series (*g' and *g'h) likewise became sibilants. Some examples:
PIE root ok'to- k'erd- g'r̥əno- ghel-
meaning eight heart corn gold, yellow-green
English (Germanic)* eight heart corn gold yellow
German (Germanic) acht Herz Korn Gold gelb
Latin (Italic) octo cor granum ** helvus
Irish (Celtic) ocht croí ** ** **
Greek (Hellenic) oktō kardia ** chrusos chlōros
Sanskrit (Indo-Aryan) aSTan śrad- ** hiraNya hari
Bosnian (S.Slavic) osam srce zrno zlato žut
Polish (W.Slavic) osiem serce ziarno złoto żołty
Slovak (W.Slavic) osem srdce zrno zlato žlty
Russian (E.Slavic) vosem' serdtse zerno zoloto zhyoltyy
- * English is grammatically Germanic, but borrows a lot of vocabulary from French. The English words shown are all Germanic in origin.
- ** I know of no native words that are obviously cognate to to the PIE root.