Ability: A concept that symbolizes or categorizes people based on a person’s ways of navigating and negotiating society – physically, emotionally, psychologically, and/or mentally—source: Tri-college libraries: Allyship and Anti-Oppression Resource Guide.
Ableism: Oppression, prejudice, stereotyping, or discrimination against disabled people based on actual or presumed disability. Source: http://www.autistichoya.com/p/definitions.html
Able Body: People who do not have any physical or sensory disability or mobility impairment.
Differently able: This can refer to any person with a disability and is usually a euphemistic phrase to avoid saying "disability" or "disabled." Source: http://www.autistichoya.com/p/ableist-words-and-terms-to-avoid.html
Otherwise stated, terms are adapted from:
Walking is an activity most people do every day without much thought, this is not the case for people who need support while walking or people who use wheelchairs. Here are some examples from Everyday Feminism- Liebowitz, Cara- http://everydayfeminism.com/2015/12/examples-walking-privilege/.