Possible Duplicates:
What security issues should I look out for in PHP
What should a developer know before building a public web site?
The project i was working on is nearly complete and near launching, but I want to make sure it is hack-proof as mine friend/partner thinks we have some enemies those can hire smart hackers to make the site down.
And if running my site securely under HTTPS, will help , will it be hard on CPU if I have a lot of users ?
Please tell me all security checks that are needed.