Do you need data from a graph/plot on paper?
First scan and crop the plot using a scanner.
Graph in raster format (JPG/GIF/TIFF):
1. For just a few points, use cursor x,y coordinates to read off values
2. Use a graph digitizer program to extract points (RECOMMENDED)
Free online: Web Plot Digitizer - automatically extracts data in CSV format, can handle non-orthogonal axes
Plot in PS/EPS format
1. Open in text editor and examine file for list of coordinates.
Remember that values will be relative to an origin point.
2. Examine other output PS files from graph software to familiarize with output format.
3. Try opening in Inkscape and examine paths using XML editor
Scan in table into GIF format then use OCR (optical character recognition) software to identify text in table. Scanners are located in MSL on the 1st and 2nd floors.
PDF Format (born digital, not scanned)
1. Convert PDF to ascii text. In Adobe Reader, use "Save As", "Text".
Additionally, there are many online and free programs such as:
2. Try highlighting and pasting into new document
Raster Image Format (JPG/GIF/TIFF)
1. Use OCR software to identify and retrieve text.