When reading, if you see a word or something you expounded just select it and click on Wiki. When done exploring, click "done" to return to the position you left.

This is from kindle. I find the buying experience just great. The difficult time is finding a book but that is because there are so many out there. From amazon, using their "one click" I can click on it and it immediately downloads to my iPad . Fun actually. I pay from $2.99 to $14.00

If we don't count our blessings
We are just wasting our time