# ROOT/PROOF/XROOTD

First you should be familiar with ROOT,PROOF and XROOTD.

Now we will give some introduction for them.

## ROOT

ROOT is a framework for data processing, born at CERN, at the heart of the research on high-energy physics. Every day, thousands of physicists use ROOT applications to analyze their data or to perform simulations.

* Processing data with ROOT (to learn about the interactive and batch use of ROOT)

* Analyzing data with ROOT (about histograms and trees; mathematical and statistical tools)

* Showing results with ROOT (explaining pads, 2D and 3D graphics, and the GUI editor)

* Simulation in ROOT (about the virtual Monte Carlo and the geometry packages)

* ROOT I/O (explaining how to use ROOT files and trees, and how to access data from d/b or other nodes)

You can get more detail information from:

http://root.cern.ch

## PROOF

* Parallel ROOT Facility

* Interactive parallel analysis on a local cluster

* PROOF itself is not related to Grid

----Can be used in the Grid
----Can access Grid files

* The usage of PROOF is transparent

----The same code can be run locally and in a PROOF system (certain rules have to be followed)

* PROOF is part of ROOT

You can get more detail information from:

http://root.cern.ch/drupal/content/more-about-proof

## XROOTD

XROOTD is a file system and Xrootd provides a Posix I/O interface.

You can get more detail information from:

http://xrootd.slac.stanford.edu