Most of time we have heard about software key logger. This software key-logger activates once Operating system starts but here is Hardware key-logger it will log every key stroke from the moment computer is turned on.Typically the memory capacity of a hardware keylogger may range from a few kilobytes to several gigabytes, with each keystroke recorded typically consuming a byte of memory. So beware of such device in public system before using sensitive data and secure web-pages like Internet banking. Here is types of Hardware key-logger.The first one is very simple it can be used with keyboard port very easily.

 
1. A Regular Hardware Keylogger is used for keystroke logging by means of a hardware circuit that is attached somewhere in between the computer keyboard and the computer. It logs all keyboard activity to its internal memory which can be accessed by typing in a series of pre-defined characters. A hardware keylogger has an advantage over a software solution; because it is not dependent on the computer's operating system it will not interfere with any program running on the target machine and hence cannot be detected by any software. They are typically designed to have an innocuous appearance that blends in with the rest of the cabling or hardware, such as appearing to be an EMC Balun. They can also be installed inside a keyboard itself (as a circuit attachment or modification), or the keyboard could be manufactured with this "feature". They are designed to work with legacy PS/2 keyboards, or more recently, with USB keyboards. Some variants, known as wireless hardware keyloggers, have the ability to be controlled and monitored remotely by means of a wirelesscommmunication standard. 
2. Wireless Keylogger sniffers - Collect packets of data being transferred from a wireless keyboard and its receiver and then attempt to crack the encryption key being used to secure wireless communications between the two devices.
3. Firmware - A computer's BIOS, which is typically responsible for handling keyboard events, can be reprogrammed so that it records keystrokes as it processes them.
4. Keyboard overlays - a bogus keypad is placed over the real one so that any keys pressed are registered by both the eavesdropping device as well as the legitimate one that the customer is using.^[

 Here are few Security tips on day to day Information security related aspects

Be careful while downaloding applications through bluetooth or as MMS attachment . They may contain some harmful software which will affect the Mobile phone

1) Delete the MMS mesage receiver from and unknown user without opening it
2) Read the mobile phone operating instaruction carefully mainly regarding the security,pin code setting,bluethooth setting,infrared setting and procedure to downlaod an applications
3) Keep the Bluetooth connection in an invisible mode or hidden mode ,unless you need to use

Know the risk and take precaution before opening your Wi-fi Network to others
1) Use a strong password and google wireless encryption.
2)Don't broadcast your SSID and MONITOR your network for intruders
3) Shut down the network when its not being used and your wireless network interface also

Always used latest verion of browser and update daily
1)Remove the remember password option and enable all the security option that are avaliable in browser
2) Always perform transaction like online shoping,banking in secured and trusted site
3)Always delete cookies before and after financial transaction.

Alwasys use Strong(hard to guess) and easy to remember password
1)Always have minumum 8 character with combination of alphabet,lowercase,uppercase,number and special character
2)Use different pasword for different sccounts and never use last three used passwords
3) Never write your passwords anywhere
4)Use passphrases and simple keys to build as many as password such as I LoveMycountry ~ ILov5My3ountry
here keys for e=5 and c=3