How to Secure your Yahoo Mail?

There are many hackers online in the internet some act good while others carry out to trick people for money.isn't it? I put my yahoo mail a "sign in seal" to protect from hacker.What is a sign in seal? It is a secret message or image that you create to protect your yahoo account from phishing.Phishing means to steal your password and personal account information.Phishers create fake website similar to yahoo to trick in disclosing user name and password.How to create a "sign in seal" ?
Go to yahoo mail site and you will notice in the log in area "sign in seal" in the upper right corner.

Create a text seal... Type a short, secret message for this computer
21 character max

* Create a unique message that everyone using this computer will recognize—for example, your street address.
* Don't include your ID or password!

Upload an image... Select an image from this computer to use

* Choose a photo that everyone using this computer will recognize.
* It can be JPEG, JPG or GIF and should be under 2MB in size.
* Tip: Use a close-up that will look good when at small size.

Note.If you have two or more personal computer you should create one sign in seal in each computer.