Because switches are such basic devices, a switch interface is usually needed to tell the computer which function it should be performing. For example, a switch interface would be programmed to tell the computer that when a user hits the switch, it should activate the Enter key on the keyboard.
There are many switches available with unique features that it can be difficult to navigate the most important specs to know before you buy a switch. Here are a few things to keep in mind when you are buying a switch:
Recording: Do you want a switch that records a message to play back whenever it is activated? Recording a message such as "Nice Job!" can be a reinforcement for a user who is unsure of whether they actually activated the switch. Other switches have extended recording time to play back when the switch is activated, like a unique phrase or detailed message. Keep in mind a switches ability to record and whether the length of the recording is appropriate for your needs.
Auditory Feedback: Even if you decide you don't need to record a spoken message for your switch, auditory feedback can be important. For most switches, the auditory feedback is in the form of a loud clicking sound so the user knows when they have activated the switch.
Switch Sensitivity: The more sensitive a switch is, the easier it is to activate the switch. For users with less mobility, a more sensitive switch makes it easier to activate. For others who have trouble with muscle control, a more sensitive switch may be activated too easily when the user doesn't intend to.
Size: Smaller switches can be placed together or in less conspicuous places, such as on a wheelchair. Larger switches can be easier to activate, but take up a larger space if multiple switches are needed. Switches with bigger surface areas can also be difficult to attach to wheelchairs.
Wireless: Although slightly more expensive, wireless switches can be a lifesaver for applications where a switch is needed across the room or to be passed among multiple users.
We've only addressed the basic button-type switches. There are also sip-puff switches, foot switches, and others for different needs.