英语阅读理解

In order to be rewarded with rankings for your links, Google needs to “know they exist”. This is why every link is pinged and we use a proprietary system for the best indexing performance. 

Q: What does "they" in "know they exit" refer to?

We are always focused on getting results for your products exposure and run a tight ship, so your investment is with a lean but result oriented firm.

Q: What are the meanings of  "tight ship" and "lean"?