Mathematica lets you import data in any format, then manipulate it using powerful and flexible functions.
This reads image data from a file.
This visualizes the data as a density plot.
Here the data is successively shifted to the right.
This applies an image filter to the data.
Here is a contour plot of the data.
This is the distribution of gray levels in the data.
Here is a 3D plot based on the data.
Mathematica can work with data of any kind -- not just numbers.
This reads in all the words in a large English dictionary.
This selects words that are palindromes with length more than 4.
This is a plot of the number of words of each length.
Mathematica also has full support for sparse arrays.
This represents a million-by-million identity matrix.