What is Twitter API and why does it keep popping up?

[Joshua Parnell]

you've downloaded a virus. any program that does not allow you to leave that window without completing an action or killing the process (short of windows shell programs) is likely a virus.

API stands for Application Programming Interface. Twitter publishes it's API so that you may include twitter functions in 3rd party software (such as an iPhone app that lets you post your tweets to twitter from your iPhone). If a virus is trying to ask for your Twitter login information (username/password) it's likely trying to steal your credentials to try them on other places. Sometimes its just getting your myspace and facebook accounts, though most of the time they're trying to access your email so that they can steal banking, paypal, and other info to steal your identity. This type of attack is usually called spear phishing when you receive emails like this, but it looks like somebody got smart with it and is trying to use a well-trusted social media to steal your identity.

i read somewhere 79% of users use the same email and same password for everything they sign up for.

I'd take your computer and have a deep virus/root kit scan. if you dont know how to do it, take it to best buy or a local computer expert shop and have them do it. for now, i wouldnt log into anything, as they could have also installed a keylogger that reports all sites and all keystrokes made on your keyboard along with the API from twitter.