LabPlot is a KDE-application for interactive graphing and analysis of scientific data. LabPlot provides an easy way to create, manage and edit plots. It allows you to produce plots based on data from a spreadsheet or on data imported from external files. Plots can be exported to several pixmap and vector graphic formats.
LabPlot2 is a complete rewrite of LabPlot1 and lacks in the first release a lot of features available in the predecessor. On the other hand, the GUI and the usability is more superior as compared to LabPlot1 and there are several new features that were not available in LabPlot1.
For a brief history about the beginning of LabPlot2 read the interview on dot.kde.org. See also a recent blog that demonstrate a couple of LabPlot2′s features.
LabPlot1 is a KDE3-application with a long history and a great number of releases. See the Features-site for the list of features and capabilities of LabPlot1.