Two types of synonyms in Oracle: Private Synonyms and Public Synonyms.
A synonym is an alternative name (Alias) for objects such as tables, views, sequences, but remember this alias name can't be the SQL Keyword
A synonym is an alternative name for objects such as tables, views, sequences, stored procedures, and other database objects
synonym is an alternative name for objects such as tables views sequences stored procedures and other database objects. A synonym (synonym-name) is an alias for an object (such as a table). The object does not need to exist at the time of its creation. Synonyms can't be used in a drop and truncate statements. If this is tried it results in a ORA-00942: table or view does not exist.