Black box testing is also termed as functional testing. It ignores how the internal functionality of a system works and depends only what are the outputs on specified inputs. Source code availability is not an important in back box testing.
Black box testing is testing in which tester do not need to understand the coding of project. It is just test 'is it fuctioning Ok'
Software testing is of following types.
Blackbox testing: This is performed by the test
engineers on the front end of the application.
Test engineer's are least bother about source
code. They validates only through UI(user
interface) by giving the inputs and validating the application weather working as per client requirements or not.
Blackbox testing is done by test engineer's manually or can be done by using automation tools.
"Hope for the best.. Prepare for the worst.."
At first you learn the testing concept then only you can apply it.. plz go through the below link for ur ref..