BEWARE OF KEYLOGGERS
If you found a black device or adapter in between CPU PS/2 or USB PORT and KEYBOARD CONNECTOR as shown in the picture, your privacy data like PASSWORDS, BANK TRANSACTIONS, CREDIT CARD INFORMATION, ONLINE MONEY TRANSACTIONS are in danger. When you enter your valuable data through keyboard these keyloggers captures every keystroke and can be misused by some other people like hackers.
These are called HARDWARE KEYLOGGERS, and software keyloggers also available. A good antivirus can only detect and clean the software keyloggers.
Further to that WIRELESS KEYLOGGERS, USB KEYLOGGERS also present in the modern world. Verdict is don't share important data or online money transcations CYBER CAFE's. Use browsing centers cautiously..