I am not quite clear about the details.

The difference between B and strong: B only changes the style of the content of the target element (changed to bold or bold), while strong indicates enhanced tone, just like <em> in a blind browser, it indicates the enhancement of the tone, but the form of this enhancement on the surface is bold. In fact, this enhancement can also be changed to something else, such as underline or italic.

Capture, target, and bubble: If a Dom is bound to multiple events, if the third parameter in addeventlistener is true, false, or not set, the sequence of the DOM event occurs, first, the listener with the true parameter is searched sequentially (first, the listener with the true parameter is executed, and then the listener with the true parameter is searched from the root node). If yes, the listener is executed first, this is what needs to be done first in the capture phase, and then the target event, which is the current element of the event. Whether the element is false or other, the event function of the element will be executed; finally, it is a listening event of Non-true and target elements. All other parameters with or without false parameters are executed one by one. This is the event bubble stage.

JS closure concept: Simply put, a func contains a declaration to define an internal function inner. If the func calls this inner externally, a closure is formed.

Title and H1: These two Dom are very important for SEO search, but H1 cannot appear frequently in the same web page, which will dilute the importance of H1

SetTimeout (func, 1000): If there is no other setTimeout defined in func and the setTimeout is executed externally, the func will be executed in 1000 milliseconds, because setTimeout is executed once by default.

I am not quite clear about the details.