R is an extremely versatile language. Download it from here and then use the lovely R Studio to make it more useful for you.
Now, one of the tasks we put R to in our book was to topic model materials. A basic script that will do this lives here: https://github.com/shawngraham/R/blob/master/topicmodel.R (right-click on the ‘Raw’ button and save as ‘topicmodel.R’; this ‘script’ can then be opened in R Studio and you can alter it to suit your own needs, point to your own materials. In a class I (SG) taught in the Winter 2015 term, I used this basic script in conjunction with the wonderful materials that Melodee Beals has shared online pertaining to the ‘Colonial Newspapers Database‘. I altered it to grab those materials directly from the web (first archiving a copy on my own github – here’s the raw R script), and then do a bit of exploratory text analysis and topic modeling. The step-by-step exploration is at http://hist3907b-winter2015.github.io/module4-holes/tm-CND.html. Similarly, I explored the Grand Jury documents from Ferguson Mo. via this same script: https://github.com/shawngraham/ferguson.