1- Created using object keyword.
2- Creation of instance is not possible in case of singleton objects.
3- Inheritance is allowed, i.e. it can extend class and traits.
4- To excess members of Singleton object, we will use the singleton object’s name dot members name.
5- The method in the singleton object is globally accessible.
6- You are not allowed to pass parameter in the primary constructor of singleton object.
7- In Scala, a main method is always present in singleton object.