differences between standard fields and custom fields

SNO	Standard Fields	Custom Fields
1	These are ready made  fields which are provided by salesforce by default(id,name created by,last modified by,owner)	Base on the project requirement salaesforce developer/admin can create their own required fields inside the object which are called custom object
2	We can customize the standard fields based on the need but we cant remove the standard fields	We can customize/remove the custom fields when its no longer used
3	We cant create any more standard fields any more	We can create one/more custom fields inside object upon needed 1 in free developer edition : 500 maximum objects 2. unlimited edition : 800 custom fields
4	Each standard field contains 2 properties 1.      Filed label : represents the fields static tet to be visible inside the user interface 2.       Field Name : represents the actual column inside the table	Each custom filed contains 2 properties 1 Filed label :represents field static text o the UI 2 API Name : represents actual name inside the table
Note : always we have to use field name to interact with the object, through programming
5	Standard fields available for both standard and custom objects	Custom fields can be applicable for both standard/custom objects
6	Standard fields name looks like as normal (ex : name id,rating etc)	Custom fields name will be post prefix’s with ‘__c’ __c à represents the custom filed