Neigh: A high-pitched, drawn-out sound, often used for communication between horses, especially to call to each other.
Whicker: A short, sharp sound, usually used to express excitement or anticipation.
Snort: A forceful expulsion of air through the nostrils, used to express fear, annoyance, or excitement.
Whinny: A softer, shorter version of a neigh, often used to express affection or to get attention.
Nicker: A soft, low-pitched sound, often used to communicate with their foals or to show affection.
Squeal: A high-pitched, piercing sound, usually made in response to pain or fear.
Roar: A deep, booming sound, usually made by stallions to assert dominance.
Grunt: A low, guttural sound, often made when the horse is exerting effort, such as during a race.
Blow: A forceful expulsion of air through the nostrils, often accompanied by a head toss, used to clear the nasal passages.
Click: A sharp, percussive sound made by the horse's tongue, often used as a way of communicating with other horses or with their handler.
In addition to these basic sounds, horses can also use their body language and facial expressions to convey a wide range of emotions.