Objects in Salesforce

Salesforce objects are like database tables which will allows to store records/data in salesforce organization.

They are three types of objects: 

1. Standard Objects

2. Custom Objects

3. External Objects

1. Standard Objects:

These objects are created by salesforce itself which will support developers/admins to use in different types of cloud applications like (Sales cloud, Service cloud, Marketing cloud etc..,). API Name of object will not contain any suffix as shown below.

Important Standard Objects are:

Account, Case, Contract, Lead, Opportunity, Contact, User

2. Custom Objects:

These objects are created by us when the requirement is not fulfill by standard objects or whenever it doesn't meet the criteria we need, we can build ourselves to suit our own specific needs, for example in bank projects agent needs to store loan information in Loan custom object.

API Name of custom object will suffix with __c as shown below.

3. External Objects:

These objects are almost similar to custom objects which we can use in Visualforce pages, Apex, Custom Tab, SOQL, SOSL,  but records will store outside of salesforce organization like in Oracle, SAP etc.., 

Each external object will connect with external data source which will specifies to connect to external system, so we don't have to maintain records again in Salesforce and we can access data on demand through Salesforce connect adaptors (Cross -Org, OData 2.0, OData 4.0, Custom Adapter created visa Apex).

API Name of custom object will suffix with __x as shown below.