If in doubt, read the software license. Most software licenses say the software may not be used on multiple computers or transferred to other users. There are exceptions, but they are rare.
Here is an example: the
Software License Agreement for Microsoft Office 2013. It is quite long, so I’ll just quote a few key sentences:
*“We do not sell our software or your copy of it – we only license it.”
“We grant you the right to install and run that one copy on one computer (the licensed computer) for use by one person at a time, but only if you comply with all the terms of this agreement.”
“You may not transfer the software to another user.”
“You may not …] publish, copy (other than the permitted backup copy), rent, lease, or lend the software.”
“You may order or download a backup copy of the software from
microsoft.com/office/backup. You may not distribute the backup copy of the software. You may use it only to reinstall the software on the licensed computer.”*
So, like I said, just read the software license agreement and that should tell you what would constitute stealing.
Also, as the previous poster noted, free software has more flexible or generous licensing. Some such license agreements explicitly allow copying and distribution, usually with the provision that the software be passed on without modification.
