TeX is a computer program for typesetting documents, created by D. E. Knuth. It takes a suitably prepared computer file and converts it to a form that may be printed on many kinds of printers, including dot-matrix printers, laser printers and high-resolution typesetting machines. A number of well-established publishers now use TeX in order to typeset books and mathematical journals. LaTeX, written by L. B. Lamport, is one of a number of `dialects' of TeX. It is particularly suited to the production of long articles and books, since it has facilities for the automatic numbering of chapters, sections, theorems, equations etc., and also has facilities for cross-referencing. It is probably one of the most suitable version of LaTeX for beginners to use.

GRE is NOT an english proficiency test like ielts / toefl: its a graduate admission measurement test (measures verbal reasoning, quantitative reasoning, critical thinking, and analytical writing skills), based on which scholarship is determined, especially in U.S. universities. Check the official site for general overview.

When I was in 2nd year of my undergrad in Dhaka University, my elder brother got me a gift which he bought for me while coming back after finishing his course works in U.S.  The gift was a thin book and the title of the book was sort of funny - "The Little SAS Book: A Primer" written by two ladies Lora D. Delwiche and Susan J. Slaughter.

Survival analysis got easier than ever since the time Therneau wrote the Survival package for S-plus/R. There have been several extensions of this package.

Video tutorials on R (parallel to s-plus) specially made for newbies are available via youtube. This starts with the topics like

Vector arithmetics