Properties and Attributes are treated similar by IE 8 and below.
Do they mean same?
@all who believes that they are same:
NO.
Properties and Attributes of an HTML element are not the same.
From DOM point of view: Properties are private variables and Attributes are stored in a NamedNodeMap stored as the childNode of the HTML elements
From JavaScript point of view (Implementation): var elem = document.getElementById("ID");
elem.prop = somevalue; //accessing properties
elem.getAttribute("attributeName"); //accessing attributes : getters elem.setAttribute("attributeName","value"); //accessing attributes : setters
Refer to my other answer for implementation details.