How do Confirmation and Popup Warnings work?

When you go to a site, sometimes there are Service Agreements and Mature Age content popups that appear where you have to confirm to accept the terms or that you confirm you are of mature age or you can select to decline and be redirected to another page.

How do these systems work. Is it just a temporary wall or is every person that confirms or agrees, their IP or account details are stored in a database.

If the latter, does a website really need to store confirmation information for legal reasons or will a popup wall be good enough??

Some Examples:
- a blog which contains some mature topics of discussion and require mature age confirmation
- a website that when users enter, they must confirm in the popup to the websites terms and conditions
- an order of product online and user confirms their online order

If you can think of any other examples, please feel free to add.

Thanks

This is really an HTML question. See the 'target' attribute of <a> tags.

The underlying mechanisms [edit] of making the actual popup itself [/edit] are either HTML or Javascript questions, depending on how you make them work.

As for the reasoning it's often about reducing liability or about ensuring users cannot get away with harming the site (as an entity) or its content.

Naturally, IANAL and you should consult one if you have serious questions about this.


Generally you don't need a record of them consenting: the fact that they made it through the rest of the process is proof enough.


Though often ineffective and arguably worthless, the gate limits the website's liability in terms of (hypothetically) having shown adult content to minors. Think of it like plausible deniability.


They often include terms which will prohibit a user from exploiting the open nature of the web (such as scraping content and offering it elsewhere) and in essence give the website recourse if the user acts like a douche.


Less legal more "we recognize that sometimes users make mistakes and we want to reduce the amount of problems resulting from mis-clicks or bad information". Without the confirmation a particularly abusive user could raise hell if they "accidentally" did something harmful, like to themselves or their reputation. It gives the website operators the chance to say "you confirmed the purchase so too bad".

The result of the prompt is then often stored in a "session variable" for the duration of the visitors stay on the site ("session").

For a session variable to work there will be a server side data store with each visitors information identified by some id which is also issued to the visitors browser in the form a cookie.

On subsequent requests the value in the cookie is sent back to the website and the web app can then access the user's original information (namem 'I agree', 'I am older than ...' etc) and make an appropriate choice

PHP has some very nice session support:

Just call the session_start() function at the top of every page you want to use session variables on, then use the super-global $_SESSION variable as an array

When the user accepts the prompt a cookie is set indicating that they've accepted it. If the cookie is present when they visit the site, then the prompt isn't shown again.

Use sessions or cookies.


Store the information in a database.

To send the data from the client, you would either use a traditional form or ajax (use post for both).

I would just like to point out that recently a website of a popular "XXX" channel was done by the authority for providing mature content to children. They said that simply asking the users to confirm if they are over 18 is not a proper way to control access!

I am not sure how this ruling affects other blogs though :s