Logical Joins: INNER JOIN, RIGHT/LEFT OUTER JOIN, CROSS JOIN, OUTER APPLY. This joins are written by the user.
Physical Joins: Nested loop, merge join and hash join is common operators which we will see in execution plan as long as query contains any logical joins (inner join, outer join, cross join, semi join). These three joins are called Physical Joins.
In below example I have executed query against AdventureWorks database with Inner Join. You can see the Nested Join in Execution Plan.