Secure instant messaging is a form of instant messaging.

Both terms refer to an informal means for computer users to exchange messages commonly referred to as "chats".

Instant messaging can be compared to texting as opposed to making a mobile phone call.

In the case of messaging, it is like the short form of emailing.

Secure instant messaging is a specialized form of instant messaging that along with other differences, encrypts and decrypts the contents of the messages such that only the actual users can understand them.

Windows Live Messenger (formerly MSN Messenger) is a discontinued instant messaging client developed by Microsoft for Windows, Xbox 360, BlackBerry OS, iOS, Java ME, S60 on Symbian OS 9.x, and Zune HD.

It connected to the Microsoft Messenger service while also having compatibility with Yahoo! Messenger and Facebook Messenger.

The client was first released as MSN Messenger on July 22, 1999, and was marketed under the MSN branding until 2005 when it was rebranded under Windows Live and has since been officially known by its present name, although its previous name was still used colloquially by most of its users.

In June 2009, Microsoft reported the service attracted over 330 million active users each month, placing Messenger among the most widely used instant messaging clients in the world.

Instant messaging (IM) is a type of online chat that offers real-time text transmission over the Internet.

A LAN messenger operates in a similar way over a local area network.

Short messages are typically transmitted bi-directionally between two parties, when each user chooses to complete a thought and select "send".

Some IM applications can use push technology to provide real-time text, which transmits messages character by character, as they are composed.

More advanced instant messaging can add file transfer, clickable hyperlinks, Voice over IP, or video chat.

Freeware is software that is available for use at no monetary cost.

In other words, while freeware may be used without payment it is most often proprietary software, as usually modification, re-distribution or reverse-engineering without the author's permission is prohibited.

Two historic examples of freeware include Skype and Adobe Acrobat Reader.

There is no agreed set of rights or a license or an EULA which would define "freeware" unambiguously; every Freeware publisher defines their own rules for their Freeware.

For instance, redistribution of Freeware by third-parties is often permitted but there is a significant portion of Freeware which prohibits redistribution.

A mobile device (or handheld computer) is a small computing device, typically, small enough to hold and operate in the hand and having an operating system capable of running mobile apps.

These may provide a diverse range of functions.

Typically, the device will have a display screen with a small numeric or alphanumeric keyboard or a touchscreen providing a virtual keyboard and buttons (icons) on-screen.

Many such devices can connect to the Internet and interconnect with other devices such as car entertainment systems or headsets via Wi-Fi, Bluetooth or near field communication (NFC).

Integrated cameras, digital media players, mobile phone and GPS capabilities are common.

Power is typically provided by a lithium battery.