A Hat in Time: Button/Key Names

In the UDK Docs, there’s a section for these buttons, so here it is:
Alphanumeric

• A – Letter A.
• B – Letter B.
• C – Letter C.
• D – Letter D.
• E – Letter E.
• F – Letter F.
• G – Letter G.
• H – Letter H.
• I – Letter I.
• J – Letter J.
• K – Letter K.
• L – Letter L.
• M – Letter M.
• N – Letter N.
• O – Letter O.
• P – Letter P.
• Q – Letter Q.
• R – Letter R.
• S – Letter S.
• T – Letter T.
• U – Letter U.
• V – Letter V.
• W – Letter W.
• X – Letter X.
• Y – Letter Y.
• Z – Letter Z.

Numbers

• one – One.
• two – Two.
• three – Three.
• four – Four.
• five – Five.
• six – Six.
• seven – Seven.
• eight – Eight.
• nine – Nine.
• zero – Zero.
• NumPadOne – Numpad one. (If NumLock is enabled, these won’t activate.)
• NumPadTwo – Numpad two. (If NumLock is enabled, these won’t activate.)
• NumPadThree – Numpad three. (If NumLock is enabled, these won’t activate.)
• NumPadFour – Numpad four. (If NumLock is enabled, these won’t activate.)
• NumPadFive – Numpad five. (If NumLock is enabled, these won’t activate.)
• NumPadSix – Numpad six. (If NumLock is enabled, these won’t activate.)
• NumPadSeven – Numpad seven. (If NumLock is enabled, these won’t activate.)
• NumPadEight – Numpad eight. (If NumLock is enabled, these won’t activate.)
• NumPadNine – Numpad nine. (If NumLock is enabled, these won’t activate.)
• NumPadZero – Numpad zero. (If NumLock is enabled, these won’t activate.)

Special Characters

• Tab – Tab.
• Tilde – ~.
• Underscore – _.
• Equals – =.
• Backslash – \.
• LeftBracket – [.
• RightBracket – ].
• Enter – Enter or Numpad enter.
• Semicolon – ;.
• Quote – ‘.
• Comma – ,.
• Period – ..
• Slash – /.

Special Keys

• Escape – Escape.
• ScrollLock – Scroll lock.
• Pause – Pause.
• CapsLock – Caps lock.
• LeftShift – Left shift.
• RightShift – Right Shift
• LeftControl – Left control.
• LeftAlt – Left alt.
• RightAlt – Right alt.
• RightControl – Right control.
• Left – Left.
• Up – Up.
• Down – Down.
• Right – Right.
• Home – Home.
• End – End.
• Insert – Insert.
• PageUp – Page up.
• Delete – Delete.
• PageDown – Page down.
• NumLock – Num lock.
• PageDown – Page down.
• SpaceBar – Space bar (Space also works).
• Divide – Numpad /.
• Multiply – Numpad *.
• Subtract – Numpad -.
• Add – Numpad +.
• Decimal – Numpad decimal.

Function Keys

• F1 – Function one.
• F2 – Function two.
• F3 – Function three.
• F4 – Function four.
• F5 – Function five.
• F6 – Function six.
• F7 – Function seven.
• F8 – Function eight.
• F9 – Function nine.
• F10 – Function ten.
• F11 – Function eleven.
• F12 – Function twelve.

Similarly, the UDK Docs have references for the mouse inputs:

• LeftMouseButton – Left mouse button.
• RightMouseButton – Right mouse button.
• ThumbMouseButton – Primary mouse thumb button.
• ThumbMouseButton2 – Secondary mouse thumb button.
• MouseScrollUp – Mouse wheel scrolling up.
• MouseScrollDown – Mouse wheel scrolling down.
• MouseX – Mouse movement on the X axis.
• MouseY – Mouse movement on the Y axis.

The one catagory that the UDK does not cover is the Event Button Names. If you change your controls in the game, say, to make Space no longer Jump, calling Space won’t catch a jump. However, it will be detected if you use the Event Button Name.

• Jump – The Jump event.
• Duck – The Dive and Crawl event.
• Attack – The Weapon use event.
• Ability – The Hat use and Hat selection wheel event.
• Interact – The Interaction event.