1) The word "triangle" contains four vowels: I, A, E, and E.

2) The English alphabet has five vowels: A, E, I, O, and U.

3) The word "chocolate" contains four vowels: O, O, A, and E.

4) The first graphical web browser, Mosaic, was released in 1993 and played a key role in popularizing the World Wide Web.