SSH is short for Secure Shell. What is secure shell? Secure shell is developed by SSH communications security ltd. and this program as created mainly focuses on securing communications between two computers on a network.
Secure shell is also a program which allows you to enter the desktop of another computer through a network and to execute commands on that computer, share files and folders, duplicate their content or transfer it.
Secure shell really is one of the most safest program to actually do this, since it can isolate the communication through the other computer on insecure channels.
That being said, even if users or a hacker tries to hijack your connection and wants to intrude into the work that you are doing it will be impossible for him to actually steal the information that you are sending over the network.
The most possible thing that the “vigilante” can do is disconnect the SSH, therefore stop all process that was previously set up in motion by the user.
Of course, this doesn’t cause any damage, except for wasting your time and build frustration. SSH is highly recommended!