The "event" object is an argument of intrinsic functions such as onclick, onkeypress, etc.
In Internet Explorer, the event object is a property of the window, and has these properties (onkeypress):
altKey: false button: 0 cancelBubble: false clientX: 153 clientY: 244 ctrlKey: false charCode: 97 fromElement: null keyCode: 97 offsetX: 141 offsetY: -3 reason: 0 returnValue: undefined screenX: 191 screenY: 393 shiftKey: false srcElement: [object INPUT] srcFilter: undefined target: [object INPUT] toElement: null type: keypress x: 153 y: 244
In Mozilla/Netscape, the event is an argument to an event handler, and has these properties:
type: keydown target: [object HTMLHtmlElement] currentTarget: [object Window] eventPhase: 3 bubbles: true cancelable: true timeStamp: 2115648847 stopPropagation: function stopPropagation() { [native code] } preventDefault: function preventDefault() { [native code] } initEvent: function initEvent() { [native code] } view: [object Window] detail: 0 initUIEvent: function initUIEvent() { [native code] } altKey: false ctrlKey: false shiftKey: false metaKey: false CAPTURING_PHASE: 1 AT_TARGET: 2 BUBBLING_PHASE: 3 originalTarget: [object HTMLHtmlElement] preventBubble: function preventBubble() { [native code] } preventCapture: function preventCapture() { [native code] } MOUSEDOWN: 1 MOUSEUP: 2 MOUSEOVER: 4 MOUSEOUT: 8 MOUSEMOVE: 16 MOUSEDRAG: 32 CLICK: 64 DBLCLICK: 128 KEYDOWN: 256 KEYUP: 512 KEYPRESS: 1024 DRAGDROP: 2048 FOCUS: 4096 BLUR: 8192 SELECT: 16384 CHANGE: 32768 RESET: 65536 SUBMIT: 131072 SCROLL: 262144 LOAD: 524288 UNLOAD: 1048576 XFER_DONE: 2097152 ABORT: 4194304 ERROR: 8388608 LOCATE: 16777216 MOVE: 33554432 RESIZE: 67108864 FORWARD: 134217728 HELP: 268435456 BACK: 536870912 TEXT: 1073741824 ALT_MASK: 1 CONTROL_MASK: 2 SHIFT_MASK: 4 META_MASK: 8 charCode: 0 keyCode: 70 initKeyEvent: function initKeyEvent() { [native code] } DOM_VK_CANCEL: 3 DOM_VK_HELP: 6 DOM_VK_BACK_SPACE: 8 DOM_VK_TAB: 9 DOM_VK_CLEAR: 12 DOM_VK_RETURN: 13 DOM_VK_ENTER: 14 DOM_VK_SHIFT: 16 DOM_VK_CONTROL: 17 DOM_VK_ALT: 18 DOM_VK_PAUSE: 19 DOM_VK_CAPS_LOCK: 20 DOM_VK_ESCAPE: 27 DOM_VK_SPACE: 32 DOM_VK_PAGE_UP: 33 DOM_VK_PAGE_DOWN: 34 DOM_VK_END: 35 DOM_VK_HOME: 36 DOM_VK_LEFT: 37 DOM_VK_UP: 38 DOM_VK_RIGHT: 39 DOM_VK_DOWN: 40 DOM_VK_PRINTSCREEN: 44 DOM_VK_INSERT: 45 DOM_VK_DELETE: 46 DOM_VK_0: 48 DOM_VK_1: 49 DOM_VK_2: 50 DOM_VK_3: 51 DOM_VK_4: 52 DOM_VK_5: 53 DOM_VK_6: 54 DOM_VK_7: 55 DOM_VK_8: 56 DOM_VK_9: 57 DOM_VK_SEMICOLON: 59 DOM_VK_EQUALS: 61 DOM_VK_A: 65 DOM_VK_B: 66 DOM_VK_C: 67 DOM_VK_D: 68 DOM_VK_E: 69 DOM_VK_F: 70 DOM_VK_G: 71 DOM_VK_H: 72 DOM_VK_I: 73 DOM_VK_J: 74 DOM_VK_K: 75 DOM_VK_L: 76 DOM_VK_M: 77 DOM_VK_N: 78 DOM_VK_O: 79 DOM_VK_P: 80 DOM_VK_Q: 81 DOM_VK_R: 82 DOM_VK_S: 83 DOM_VK_T: 84 DOM_VK_U: 85 DOM_VK_V: 86 DOM_VK_W: 87 DOM_VK_X: 88 DOM_VK_Y: 89 DOM_VK_Z: 90 DOM_VK_NUMPAD0: 96 DOM_VK_NUMPAD1: 97 DOM_VK_NUMPAD2: 98 DOM_VK_NUMPAD3: 99 DOM_VK_NUMPAD4: 100 DOM_VK_NUMPAD5: 101 DOM_VK_NUMPAD6: 102 DOM_VK_NUMPAD7: 103 DOM_VK_NUMPAD8: 104 DOM_VK_NUMPAD9: 105 DOM_VK_MULTIPLY: 106 DOM_VK_ADD: 107 DOM_VK_SEPARATOR: 108 DOM_VK_SUBTRACT: 109 DOM_VK_DECIMAL: 110 DOM_VK_DIVIDE: 111 DOM_VK_F1: 112 DOM_VK_F2: 113 DOM_VK_F3: 114 DOM_VK_F4: 115 DOM_VK_F5: 116 DOM_VK_F6: 117 DOM_VK_F7: 118 DOM_VK_F8: 119 DOM_VK_F9: 120 DOM_VK_F10: 121 DOM_VK_F11: 122 DOM_VK_F12: 123 DOM_VK_F13: 124 DOM_VK_F14: 125 DOM_VK_F15: 126 DOM_VK_F16: 127 DOM_VK_F17: 128 DOM_VK_F18: 129 DOM_VK_F19: 130 DOM_VK_F20: 131 DOM_VK_F21: 132 DOM_VK_F22: 133 DOM_VK_F23: 134 DOM_VK_F24: 135 DOM_VK_NUM_LOCK: 144 DOM_VK_SCROLL_LOCK: 145 DOM_VK_COMMA: 188 DOM_VK_PERIOD: 190 DOM_VK_SLASH: 191 DOM_VK_BACK_QUOTE: 192 DOM_VK_OPEN_BRACKET: 219 DOM_VK_BACK_SLASH: 220 DOM_VK_CLOSE_BRACKET: 221 DOM_VK_QUOTE: 222 DOM_VK_META: 224 screenX: 0 screenY: 0 clientX: 0 clientY: 0 button: 65535 relatedTarget: null initMouseEvent: function initMouseEvent() { [native code] } getPreventDefault: function getPreventDefault() { [native code] } layerX: 0 layerY: 0 pageX: 0 pageY: 0 which: 70 rangeParent: [object Text] rangeOffset: 0 cancelBubble: false isChar: false SCROLL_PAGE_UP: -32768 SCROLL_PAGE_DOWN: 32768