SSL Certificate from Certificate Authorities enhance online trust.

You can, if you like, produce your own Digital Certificate on your own computer and exchange them with your friends and colleagues. But would they be good enough for your customers and other users of your website?

Would it make sense to "co-sign" your own loan? That would not add any value. Your customers wouldn't trust or accept your home-made certificates (unless your customers were also friends or colleagues.)

As a businessperson, you listen to what potential business partners say about themselves. You also look for independent corroboration. Do they have good references? Is their money the right color?

For the same reason, your customers also want and need to verify your website. They do not want to send their confidential information to potential phishing websites. To establish this trust, Internet-facing applications, such as your website, need to have an SSL certificate signed by a trusted Certificate Authority (CA).

Unless your SSL Certificate is created by a trusted third party such as a CA, the browser won't recognize the site as verified.

A trustworthy Digital Certificate issued by a WebTrustSM compliant Certificate Authority vouchsafes your business identity. Webtrust-compliant Certificate Authorities, like Comodo, are audited annually and they store their own key information in highly-secure facilities. An SSL Certificate issued by a trusted CA creates an environment of trust in your website, assuring your users and customers that their confidential information will be transmitted securely and to the right destination.

An untrusted digital certificate isn't worth the paper it's (not) printed on.
To protect their users, all the major browsers look for certificates produced by trusted Certificate Authorities. If they can't find a certificate, or if they find a certificate, but don't trust it, the browsers give the users stern warnings.

Even if the users do not know what the warnings mean, they're afraid to continue.

Why do the browsers warn about home-made certificates? Because a Digital Certificate is not hard to make or alter. Because home-made certificates are not vetted or checked to ensure that they are only being issued to legitimate businesses.

An SSL Certificate from a trusted CA is your website's security credential. Validated SSL Certificate are embedded on the browser to let users know that the website is a safe zone. The absence of CA-issued SSL Certificate undermines your website and deters potential customers.

How is EV-SSL different from SSL