Positive and Negative Testing.

 Positive Testing:-  

positive testing laid down (determines) that your application work as expected. if an error has occurred during positive testing, test fails.

positive testing is a software testing that can be performed on your system by provide valid data input.

Negative Testing:- 

                                Negative Testing is a software testing that can be performed on the system by invalid input data.
Negative testing ensures that your application can handle invalid input or unexpected user behaviors. 

Example:-

Test case for the Gmail Login Page.

1: Positive Test Case.

1.1:- Verify that user name/email box must be available.
1.2:- Verify that username/email box must be clickable.
1.3:-Verify that username/email box must be informative(email or phone).
1.4:- Verify that email should no be start with symbol.
1.5:-Verify that cursor focus in text area.
1.6:-Verify that email should be contain number and letter.
1-7;- Verify that email should not be left blank
1.8:-verify that email should not be more than 40  characters.
1.9:-Verify that if user hit login button (now a day next button is coming) without enter username/phone/email than must be error message that "enter username/pone"

2:- Negative Test Case:-

2.1:-Verify that with valid username and invalid password are we able to login.
2.2:- Verify that invalid username and valid password are we able to login.
2.3:- Verify that as we hit login button without enter username.
2.4:- Verify that as we hit login button without enter user password.
2.5:- Verify that as we hit login button without enter username and password.

Testing Technique use for positive and negative testing.

1:-Boundary Value Analysis:-  it is one of the black test design technique. it based on testing the boundary value of valid and invalid partition. Every partition has its maximum and minimum value and these maximum and minimum value are boundary value of partition. A boundary value for a valid partition is a valid boundary value. A boundary value for a invalid partition is a invalid boundary value.

Example:-

I have a age box which accepts 18 to 56 

Boundary value Analysis
Invalid (min-10)	Valid (min,+min,-max,max)	Invalid (max+1)
17	18,19,55,56	57