小老弟英文不错，想法也不错，做事的切入点也不错！欢迎留在美国跟我们入伙！（不要介意有些中国人的冬烘劲，什么“要做码工为什么要读统计，读了统计为何要做码工”，那种是典型的冬烘先生 -- simple-minded and out of sense.）
好了，回答您的问题：
1. What are the differences between data analyst and data scientist?
A lot! Data analyst is entry-level job, for somebody who can work on data and dig out information for business support, this is will be very likely the first job you'll get. At this entry-level job, you will receive some supervision, and you'll pick up lots of experience, then you go two paths: project management or more senior level analyst.
A data scientist job will require much more! That's a job for somebody who can beat any issue with data: No data at all? He knows how to get it; Data storage and security? yes, digging out info that nobody knows? yes. Typically, this is a person with Ph training in hard-core science, lots of quant, lots of coding, and lots of critical thinking.
2. What are the main skills required to be a data analyst?
The best way to get you into the door is: SAS or R, or Both of them!:) R is a good start, you pick up R you get lots of experience at general computing. By reading the manual, you learn lots of stats, too:).
Hope it helps you any!
