Romanian is spoken by about 25 million people, primarily in Romania and Moldova.
It is an inflected language: nouns and verbs change their endings according to their syntactical use.
If you understand Italian or Spanish you will probably have little problem understanding Romanian.
Most of the words are similar, because these languages are all derived from Latin.
About 1/4 of Romanian words are not derived from Latin. Most of those are Slavic words.