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docs.it4i/anselm/introduction.md

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 Welcome to Anselm supercomputer cluster. The Anselm cluster consists of 209 compute nodes, totaling 3344 compute cores with 15 TB RAM and giving over 94 TFLOP/s theoretical peak performance. Each node is a powerful x86-64 computer, equipped with 16 cores, at least 64 GB RAM, and 500 GB hard disk drive. Nodes are interconnected by fully non-blocking fat-tree InfiniBand network and equipped with Intel Sandy Bridge processors. A few nodes are also equipped with NVIDIA Kepler GPU or Intel Xeon Phi MIC accelerators. Read more in [Hardware Overview](hardware-overview/).
 
-The cluster runs [operating system](software/operating-system/), which is compatible with the RedHat [Linux family.](http://upload.wikimedia.org/wikipedia/commons/1/1b/Linux_Distribution_Timeline.svg) We have installed a wide range of software packages targeted at different scientific domains. These packages are accessible via the [modules environment](environment-and-modules/).
+The cluster runs operating system, which is compatible with the RedHat [Linux family.](http://upload.wikimedia.org/wikipedia/commons/1/1b/Linux_Distribution_Timeline.svg) We have installed a wide range of software packages targeted at different scientific domains. These packages are accessible via the [modules environment](../environment-and-modules/).
 
 User data shared file-system (HOME, 320 TB) and job data shared file-system (SCRATCH, 146 TB) are available to users.