button
Here is an example of the button tag. It is a little bit misleading since it is a button that doesn't do anything. You would want to add some interactivity, perhaps with JavaScript.
meter
he <meter> element is cool and can take a lot of attributes. But again it is better if you have some code that can make the attribute values dynamic instead of "hardcoding" them. When you think of a meter, think of a final score for a test.
progress
The <progress> element has a very similar layout to the meter tag. The difference is that there is an assumption that there will be a progression toward 100%. This tag is often used when filling out a form that has many pages of questions.
iframe
The <iframe> element is used to next content. It is not supported equally well by all browsers. You will want to explore options such as width and height.
Bi-directional orientation - bdo
The <bdo> element is for bi-directional orientation of your text. This element can be used to change the direction of your text.
This text will be right to left