Both languages are very different from each other!

FROM WIKIPEDIA:-

Urdu is often contrasted with Hindi. Apart from religious associations, the differences are largely restricted to the standard forms: Standard Urdu is conventionally written in the Nastaliq style of the Persian alphabet and relies heavily on Persian and Arabic as a source for technical and literary vocabulary, whereas Standard Hindi is conventionally written in Devanāgarī and draws on Sanskrit. However, both have large numbers of Arabic, Persian and Sanskrit words, and most linguists consider them to be two standardized forms of the same language, and consider the differences to be sociolinguistic, though a few classify them separately. Mutual intelligibility decreases in literary and specialized contexts which rely on educated vocabulary. Further, it is quite easy in a longer conversation to distinguish differences in vocabulary and pronunciation of some Urdu phonemes. Due to religious nationalism since the partition of British India and continued communal tensions, native speakers of both Hindi and Urdu frequently assert them to be distinct languages, despite the numerous similarities between the two in a colloquial setting.

Both languages are very different from each other!

FROM WIKIPEDIA:-

Urdu is often contrasted with Hindi. Apart from religious associations, the differences are largely restricted to the standard forms: Standard Urdu is conventionally written in the Nastaliq style of the Persian alphabet and relies heavily on Persian and Arabic as a source for technical and literary vocabulary, whereas Standard Hindi is conventionally written in Devanāgarī and draws on Sanskrit. However, both have large numbers of Arabic, Persian and Sanskrit words, and most linguists consider them to be two standardized forms of the same language, and consider the differences to be sociolinguistic, though a few classify them separately. Mutual intelligibility decreases in literary and specialized contexts which rely on educated vocabulary. Further, it is quite easy in a longer conversation to distinguish differences in vocabulary and pronunciation of some Urdu phonemes. Due to religious nationalism since the partition of British India and continued communal tensions, native speakers of both Hindi and Urdu frequently assert them to be distinct languages, despite the numerous similarities between the two in a colloquial setting.

They are two different languages, but similar when spoken but still used in different areas. I guess people sometimes mixed it together. Sorry I can't explain well. I am not studying urdu nor hindi but I have friends from India.