How do we Know That There was a Moon Landing?

https://www.quora.com/To-someone-who-believes-in-the-moon-landing-can-you-break-down-all-the-reasons-you-think-it-did-actually-happen-I-m-personally-skeptical/answer/Ian-Williams-93?ch=17&oid=1477743745289055&share=f43b737d&srid=dMXD&target_type=answer