Hi Omprakash,
These parameters are self explainatery..
Time Between Password Changes (days): 2
Users can change the password in minimum interval of 2days. Means, If user change password today, he cannot change the password again in next two days.
Password Expiration Time (days): 90
If the password is not changed in 90 days, it will be expired. Users will forcefully asked to change the password forcefully
Password Expiration Warning Time (days): 20
After 70 days(means 20days before password expire) the user starts receiving a warning that the password is about to expire.
Password Life Time (days): 90
After 90 days the account is disabled, if the password still has not been changed since it expired.
Hope this clarify your doubts.
Best wishes,
Ganesh.