McGrath described exactly the most common instance of how I use the ellipsis here, to indicate I could say more, but am pausing at this point since the meaning has been made.

According to the Modern Language Association (MLA), an ellipsis should technically include spaces between the periods, thus: . . . to be clearly seen. If you use an ellipsis in a quote, it means you're dropping part of the phrase (for space and clear meaning). If you use . . . . (four dots) then the first one is the end of the previous sentence and the next three indicate that more than a few words, perhaps as much as a few sentences or paragraphs, have been dropped. They're trickier to use correctly. At some point you have to decide to simply use two quotes, rather than running two distant bits together as one.

I use the ~ to mean "about" or "approximately." I don't know where I picked it up, but it's pretty commonplace here in the U.S.

SRS