What is an sObject type in Salesforce Apex?

An sObject variable represents a row of data and can only be declared in Apex using the SOAP API name of the object.
For example:

Account a = new Account();
MyCustomObject__c co = new MyCustomObject__c();

Apex allows the use of the generic sObject abstract type to represent any object. The sObject data type can be used in code that processes different types of sObjects.

The new operator still requires a concrete sObject type, so all instances are specific sObjects.

For example: sObject s = new Account();

Thanks