They are called a CAPTCHAs.
A test to see if you are a human (no, I’m not joking)
Let’s try to explain…
I’m sure you get junk mail through the post at home. Most of it goes straight in the bin and it’s just a big waste of time and paper. You can try contacting the companies to tell them to stop sending you junk mail but they rarely take any notice so you just have to put up with it.
When you use computer messaging systems such as email you will often receive unwanted junk messages (spam) from companies trying to sell you things you don’t need or trying to scam you out of your money.
Spam messages are not sent out by humans. They are sent by automated computer systems.
The companies that provide email services such as yahoo, hotmail and google do not like spam. It wastes their money and resources to transfer and store billions of unwanted messages within their computer systems. Companies that provide email services are constantly trying to prevent junk mail / spam.
Companies that provide email accounts provide easy ways for its customers to mark unwanted messages as spam. If you receive a junk E-mail you can simply mark the sender as a spammer and you will receive no more messages from them.
Email companies also track if particular senders are being marked as spam by many people. If a certain email address is marked as spam by 1000 people then the email provider may automatically prevent messages from that email address being sent through their system. This effectively means that the email address is now useless to the spam sender.
Now this poses a problem for the spam companies. They need to keep sending out spam to keep their business running but they keep getting their email addresses blocked!
In order to keep their business running the spam company must keep registering new email accounts. They could have lots of slaves in a developing country filling out email registrations but that is too slow and costs money!
Instead, spam companies used automated computers to try to complete email registrations. As mentioned earlier, the Email companies don’t want these spam messages so they don’t want automated computers registering more email addresses.
This is why there are CAPTCHA tests. Usually CAPTCHA tests can only be solved by humans.
An automated computer trying to register an email account will not be able to figure out what the strange writing is and will not be allowed to able to complete the registration of a new email account.
Phew!
Well done if you understand this.
You dont need to know how or why we have CAPTCHAS - all you need to do is get them correct!