"Assistive technology device" means any item, piece of equipment, or product system, whether acquired commercially off the shelf, modified, or customized, that is used to increase, maintain, or improve the functional capabilities of a child with a disability. 34 CFR §300.5

"Assistive technology service" means any service that directly assists a child with a disability in the selection, acquisition, or use of an assistive technology device. The term includes:

1. The evaluation of the needs of a child with a disability, including a functional evaluation of the child in the child's customary environment;
2. Purchasing, leasing, or otherwise providing for the acquisition of assistive technology devices by children with disabilities;
3. Selecting, designing, fitting, customizing, adapting, applying, maintaining, repairing, or replacing assistive technology devices;
4. Coordinating and using other therapies, interventions, or services with assistive technology devices, such as those associated with existing education and rehabilitation plans and programs;
5. Training or technical assistance for a child with disability or, if appropriate, that child's family; and
6. Training or technical assistance for professionals (including individuals providing education or rehabilitation services), employers, or other individuals who provide services to employ or are otherwise substantially involved in the major life functions of that child. 34 CFR §300.6