There are three genders in Slovak - masculine, feminine and neuter. They're used not only for people, but also animals, objects, plants, etc. To use a noun correctly, you need to know its gender.
When consonants d, t, n, l are followed by the vowels e, i or by the diphthongs ia, ie, iu, their pronunciation is soft (ď, ť, ň, ľ), except for words of foreign origin. In modern-day language, L is usually pronounced hard, even in this position.