Some details of your system, brand name, model, desktop or laptop, CPU, RAM, age of the system.
Which OS have you installed?
What were you doing when the problem occurred
Briefly explain what is not working for you and what you were doing when the issue occurred. Have you made any recent changes to your machine? Tell us any error messages displayed.
In the topic description guide us to your problem, don't say "Help I am desperate" which tells us nothing. Give us an example 'Software Problem' for example. Also tell us what you have done to try and fix your problem.
Try and be patient, problems often take some time to research and if you are assisted, please thank the volunteer posting back if your problem has been solved telling us how it was solved....we are all learning too.
Following the above will help us to help you more quickly.