topics/linux/README.md is modified (bregman-arie#10256)

* topics/linux/README.md is modified

* topics/linux/README.md is modified

topics/linux/README.md

@@ -360,6 +360,7 @@ It contains useful information about the processes that are currently running, i
 
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 <summary>What makes /proc different from other filesystems?</summary><br><b>
+/proc is a special virtual filesystem in Unix-like operating systems, including Linux, that provides information about processes and system resources.
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@@ -433,6 +434,10 @@ Its a bit that only allows the owner or the root user to delete or modify the fi
 
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 <summary>What is sudo? How do you set it up?</summary><br><b>
+sudo is a command-line utility in Unix-like operating systems that allows users to run programs with the privileges of another user, usually the superuser (root). It stands for "superuser do.
+
+The sudo program is installed by default in almost all Linux distributions. If you need to install sudo in Debian/Ubuntu, use the command apt-get install sudo
+
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