Mouse and its type.

The mouse is an input device that is used to give the command and sometimes input to the computer. It is a small box with around ball at the bottom and more than one buttons on the top. If is held in one hand and moved across a flat surface movement of the ,mouse on a flat surface moves the ball which in turn controls movement of a cursor on the monitor. In addition to moving the cursor, the mouse can be sued to select text or commands and to manipulate data on the screen by clicking the buttons.

In other words. A device that controls the movement of the  cursor or pointer on a display screen. A mouse is a  small object you can roll along a hard, flat surface. Its name is derived from its shape, which looks a bit like a mouse, its connecting wire that one can imagine to be the mouse’s tail, and the fact that one must make it dash along s surface. As you move the mouse , the pointer on the display screen moves in the same direction. Mouse contain at least one button and sometimes as many as three, which have different functions depending on what program is running. Some newer mice also include  a scroll wheel for scrolling through long documents.

The mouse is one of the great breakthroughs in computer ergonomics because it frees the user to a large extent from using the keyboard. In particular, the mouse is important for graphical user interfaces because you can simply point to options and objects and click a mouse button. Such applications are often called point-and –click programs. The mouse is also useful for graphics programs that allow you to draw pictures by using the mouse like a pen, pencil, or paintbrush.

According to the working principle, mouse can be divided into three categories:

Mechanical

A mechanical mouse works by the mechanical action of its different parts. It has a rubber or metal ball on its underside that can roll in all directions. Mechanical sensors within the mouse detect the direction the ball is rolling and move the screen pointer accordingly.
When this mouse is rolled across a flat surface, different rollers inside the mouse move and generate electric signals. These signals are given to the computer and computer converts them into proper action on the screen.


                                                                                                      Mechanical Mouse


Opto-mechanical

The basic construction of the Opto-mechanical mouse is same as that of the mechanical mouse . only difference is in the sensing circuit used to detect the movement of the mouse. In a mechanical mouse, a detector is used to detect the distance, when it is moved on the flat surface, whereas, in an opto-mechanical mouse, a combination of LED and Photo detectors (optical sensor) are used to sense the distance traveled the mouse (motion of the ball). Most of the mouse are of this types, we are using.

                                                                                                                                                                                       Opto-Mechanical Mouse

Optical                                                                                                                                                                

Optical mouse uses a laser to detect the mouse’s movement. You must move the mouse along a special mat with a grid so that the optical mechanism has a frame of reference. Optical mica have no mechanical moving parts. They respond more quickly and precisely than mechanical and opto mechanical mice, but they are also more expensive.
In this type of mouse, instead of the normal ball and rollers, a light source and photo detector is used with a special mouse pad. When the optical mouse is moved on this special pad, light from the light source gets reflected from the pad and special photo detectors inside the mouse detect the horizontal and vertical movement based on the reflected light receive.

Based on the method used to interface or to connect the mouse to the main computer system, mouse can be divided into following categories:

Serial mouse

Serial mouse

A mouse that connects to a computer via a serial port is a Serial Mouse. This is the simplest type of connection.
A serial mouse is connected to either COM1 or COM2, i.e. any one of the available is very easy as one need to just plug in the connector attached to the mouse wire to the vacant serial port on the computer. Is has 9 pin and D type in shape.

PS/2 mouse (Bus Mouse)

The other common type of mouse is a PS/2 mouse, which plugs into a PS/2 which plugs into a PS/2 mouse port. Only difference between a bus mouse and a serial mouse is a serial mouse is connected to a serial interface card or some type of  I/O card with a serial interface option, whereas the bus mouse is connected to a special card mode just for the mouse. This interface was introduced with the IBM-PS/2 series of computers, and was therefore, called PS/2. It has 6 pin and circular type in shape.



                                                                                                    PS/2 mouse (Bus Mouse)   


USB Mouse

USB Mouse connects to USB port.
USB stands for Universal Serial Bus, and external bus standard that supports data transfer rates of 12 Mbps. A single USB port can be used to connect up to 127 peripheral devices. USB also supports Plug-and-Play installation and hot plugging.





                                                                                                                                                                                              USB Mouse

Wireless mouse

Cordless (Wireless) Mouse isn’t physically connected at all. Instead they rely on infrared or radio waves serial and bus mice, but they do eliminated the cord, which can sometimes get in the way.
In this type of mouse, everything is similar to the conventional mouse except that no cable is used to connect the mouse to the computer system. Basically there are two types of wireless mouse: Infrared wireless Mouse and Radio-controlled Wireless Mouse.

                                                            Wireless mouse
 
The infrared mouse communicates with the receiving unit connected to the main system units using infrared light. When the radio-controlled wireless mouse is moved, radio signals are transmitted by it to a special receiver unit connected to the main system. Most of the infrared Wireless Mouse and Radio-controlled wireless Mouse require the mouse to be within six feet of the receiving unit.