Error : Human action that produces incorrect result

Bug : incorrect of code caused by an error

Defect: the difference between actual result and expected 
result

Error : Human action that produces incorrect result
finded it by developer

Bug : incorrect of code caused by an error
finded it by Tester(us)

Defect: the difference between actual result and expected 
result
Finded it by Client

Error: If coding time if got any mistakes (syntax errors, 
etc) that we can call Error.

Defect : while testing application if u got any  mismatches 
(not meeting excepted results) then we report to developers 
as defect found in  that application.

Bug : If developers also agrees with that defect and going 
to fix in an application then its called bug.

bug -a fault in programm which causes the problem to 
perform in an unanticipated manner.

defect -  aAfter relesed any bug or error is found then it 
is defect.

Error It is difference between observe value and true value.

Error : it is a mistake.
Bug : Error occured at Testing Phase
Defect : Error occured at clients place.

Defect: Fault in the Design
Error: Progametic mistake
Bug: Deviation from the specification.

Error  : If a user face any kind a problem while connecting 
to the application or face exceptions in the application or 
unable to connect the third party interface.

Defect : When there is a missing requirements in the 
application (Software is missing some functionalities as 
per RS/ FS) we call it a Defect.

Bug    : When the application generates result not 
according to the functionality of the application is called 
a Bug. Functionality is implemented but results are not as 
per expected.