Animals communicate with each other by means of signs, signals or sounds transmitted by them. Communication, like a human language, they do not. Even people, communicating with each other, do not always use words. People can express their anger in an original way, shrug their shoulders as a sign of indifference, shake their heads, nod, gesticulate and much more.
Many animals with the help of signs or scent can express the same. If a horse beats a hoof or neighs, then this is a definite signal for others. Many animals are able to understand subtle sounds and signals.
Dogs can communicate in a variety of ways. They can bark and howl, growl and whine, bared their teeth or lift their paws. Each such signal is quite understandable to others and they know the purpose of such a signal in each case.
Animals communicate with each other not only with the help of gestures and sounds, but also with the help of odors. This allows the herd animals to stick together. Everyone knows how important this is for dogs.
Monkeys seem the most intelligent, but their language is not better than the rest of the animals. They use facial expressions and sounds, showing feelings of hunger, pleasure or anger. But they have nothing like human speech.
Animals understand their language from birth, a person also has to learn to talk. Animals can make appropriate signals, even if they never communicated with their own kind. But, even communicating with each other, animals express only aspirations and feelings, and do not really talk.