Think of it as a tree, rather than a straight line of evolution. It has many branches and is very comparable to a modern family tree. Now a family tree is hardly evolution, but it's a good example of how it works, just on a MUCH smaller scale. Example:
You and your siblings descended from your mom and dad, who descended from two other pairs of moms and dads (your grandparents), and so on and so forth. Now just because you are a product of your grandparents, that doesn't mean you are directly descended from them, or that they transformed into you and ceased to exist. They produced offspring that were similar to them, but still slightly different (your uncles and aunts), and those produced more offspring until finally one couple produced you. You are a product of multiple generations breeding and changing slowly over time. And you're not the only one. You could have brothers or sisters who eventually have their own kids and grandkids, and so on. Their great great great grandkids will hardly be related to your own great great great grandkids, just like we're not directly related to monkeys or chimpanzees.
Humans, like most animals, are still evolving. More and more people are never getting their wisdom teeth, because humans are still evolving a shorter jaw because we just don't use it like baboons and longer-faced animals do. Eventually humans will not even have wisdom teeth at all, it will be a thing of the past. The same is happening to our toes. Some people have one less bone in their little toe, because our toe is still shrinking. We just don't use them for anything. Someday, thousands or millions of years from now, it's possible humans will just naturally have only 4 toes, or at least less bones in them.
Now take that change, and then continue it over millions and millions of years and eventually you get something that is so physically and genetically different from where you started that it's considered a different species. That's evolution. We even have some birds today that still have claws on their wings, a glimpse into their past. Ultimately though, evolution is something that you can't just teach someone in one conversation (or Yahoo post), just like many other complex processes.