A small confusion about topics
Hello I am new to ros, I See people always use cmd_vel topic for geometry msgs. My confusion is, what is the reason of always using cmd_vel? Can't we use other topic name? Or there are some existing topics like msg, such as ros have existing msg type like Twist, odom, pose etc. If ros 2 also have some existing topics, what are they? how to find them? (Sorry for bad English).
I didn't get the second part of your question. ('or there are .....')
Thanks everyone ๐