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we will learn about colcon now

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colcon is a tool that ros2 uses in order to build the package from source

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we work in a workspace where we store the packages and the colcon build will be use to build these packages So

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here is the command in order to install

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so it is installed and now we will be creating
our first workspace remember that we pushed a

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line in The Bashrc that was the source opt
Ros and Foxy setup.bash so this is how we

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Source a terminal that was our underlay
workspace and now we will be creating

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an overlay workspace open the files create a
folder ros2_ws ros2 workspace

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now we will clone a package inside our
workspace so cd ros2_ws so

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now we are in our workspace from the terminal
and we will be cloning a package that is here

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yeah so now it has a SRC folder and then
example and then there are some code

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inside this and we will just see the package
structure the SRC folder in which we keep our

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repositories try to build this how we can
build it we there are actually two commands

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one is the colcon build
and the other is colcon build

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-- symlink - install so what is
the difference between these two commands Okay

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colcon build will be building all the packages from The
Source instead of just building if

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we add the keyword symlink install
it will also be linking the packages

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with the installation directories  build
directly colcon build -- symlink

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install is command that built the packages
faster so we will be using this command

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and now it is building our first package that
we just cloned remember that we we had just

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src folder before but after we enter the
command it has created three extra folders so

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in the build folder it builds and save the files
in binaries into this build directory and in the

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install directory it creates the file that will
be used to install and in the log solder it saved

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the log information from the different nodes
now we have build the package after building

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our workspace is still not sourced so we also
have to Source this particular workspace in

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order to run a node okay so how do we do
that by source install and set up dot bash

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using this command colcon test we can also
monitor the package about their colcon status

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do you remember how do we run a node, we
use command ros2 run package name

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and then the executable conde ros2 run
package name is the example underscore

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and node name subscriber member function
node is running now we will open up another terminal and uh

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we will type this command
this is the publisher command

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okay it is publishing and this is receiving

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okay so this is how we can
run a node from our workspace