Provides users, who are mostly people with limbs disability to input English and Chinese characters, as well as execute basic system commands on computers. The operation method includes: Step (1), showing the groupings of system commands, English letters and numbers for users to choose. Step (2) , accept the user's choice of the three menus of the system; Step (3), when the user selects the "Switch" button, a choice of six different systems, character and number will be presented will be presented to him/her. Step (4), if the user presses and holds the button for no more than three seconds, it will switch to three different interfaces, including: English letters, numbers, and system commands. If it is not the case, step (2) will be repeated. When the system is showing the English alphabet interface, the six buttons will load the character group of a-f that user have to select, confirm and execute the corresponding button according to their choice. Then, the selected letter will be displayed on the computer screen. If it is not the case, step (4) will be repeated. Similarly, when the system is showing the number interface, groupings of number from 0-9 will be loaded on the six buttons that user have to select, confirm and execute the corresponding button according to their choice. Then, the selected number will be displayed on the computer screen. If it is not the case, step (4) will be repeated. When the system is showing the system command interface, different command key will be loaded on the six buttons including shut down, logout, restart, typing, open file manager and surf the net, likewise, user have to select, confirm and execute the corresponding button according to their choice.