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Computer Mouse The computer mouse was invented in 1964 by Douglas Englehart of Stanford University.As computer screens became more popular and arrow keys were used to move around a body of text，it became clear that a pointing device that allowed easier motion through the text and even selection of text would be very useful.The introduction of the mouse，with the Apple Lisa computer in 1983，really started the computer public on the road to relying on the mouse for routine computer tasks. with several small holes in them.The wheels have a pair of small electronic light-emitting devices called light-emitting diodes mounted on either side4.One LED sends a light beam to the LED on the other side.As the wheels spin and a hole rotates by，the light beam gets through to the LED on the other side.But a moment later the light beam is blocked until the next hole is in place.The LED detects a changing pattern of light，converts the pattern into an electronic signal，and sends the signal to the computer through wires in a cable that goes out the mouse body.This cable is the tail that helps give the mouse its name.The computer interprets the signal to tell it where to position the cursor on the computer screen. 词汇： mouse pad 鼠标垫板 graphicsn.图形，图表5tAblitp workhorsen.重负荷丁作部件 shaftn.轴，杆状物 cursorn.光标 opticaladj.光学的 | 
