What is defaults in Sql Server and types of Defaults

Defaults are used when a field of columns is allmost common for all the rows for example in employee table all living in delhi that value of this field is common for all the row in the table if we set this field as default the value that is not fill by us automatically fills the value in the field its also work as intellisense means when user inputing d it will automatically fill the delhi . There are two types of defaults object and definations. Object d
eault:-These defaults are applicable on a particular columns . These are usually deined at the time of table designing.When u set the object default field in column state this column in automatically field when u left this filed blank. Defination default:-When we bind the datatype with default let we named this as dotnet .Then every time we create column and named its datatype as dotnet it will behave the same that we set for dotnet datatype.