Copyright Versus EULA
Although copyright only restricts copying, someone noticed that you typically have to copy software a couple of times in order to use it. You might copy it from the distribution media onto a hard disk, and then again into RAM to run it. Because you need extra rights to make these copies, the copyright owners reasoned that they could make you give up other rights in exchange for these copying rights, and the End User License Agreement (EULA) was born.
A lot of software these days comes with an End User License Agreement, which tells you exactly what you can and can’t do with the software. If you don’t accept the license agreement, you don’t have the right to copy the software into RAM or onto your disk, so you can’t use it. This restriction violates the spirit of copyright law, and in some jurisdictions the right to make these copies is explicitly granted by law, making EULAs of questionable legality.
In this issue, Free Software is more closely aligned than proprietary software with copyright, because Free Software licenses are not EULAs, and only control distribution. You can use Free Software without accepting any license conditions if you have legally received a copy of the software, and you’re required to accept the license only if you want to make derived works or distribute the software.
This idea can be confusing, since a lot of installation programs for Free Software have a habit of presenting the license as if it were an End User License Agreement and refusing to proceed unless you click the "I agree" button or equivalent. In some cases, the confusion is caused by the installer requiring the EULA; in others, the people who do the packaging fail to read the license for the code that they’re distributing.