It is no matter that both table having same record or how much record.
If there is some relation between table column is created then only you can say tables are linked
Like Primary key & foreign key
http://www.w3schools.com/sql/sql_foreignkey.asp
Or column from first table & second table are having some relation for eqality.
E.g first table Employee
column - empid empname depid
second table Dept
column - deptid deptname
Here two tables are linked with deptid
Suppose first table having only these two column
empid empname then there is no relation between two table.(I dont see such situation)
You should understand first what functionality you are providing then according to see database design. Then you get link between tables.
Please go through this link for relational design in database table.
http://parallel.vub.ac.be/documentation/database/tutor/