Enterprise version from internet download is always a trial version, if you want visual studio 2015 free version then you can download Visual Studio Community edition, its A free, fully-featured, and extensible IDE for creating modern applications for Windows, Android, and iOS, as well as web applications and cloud services, Visual Studio Community is free for individual developers, open source projects, academic research, education.
it has Everything you need all in one place, you can Build apps for any platform, contains Designers, editors, debuggers, profilers, in one single tool, Access to thousands of extensions, Code in C#, Visual Basic, F#, C++, HTML, JavaScript, Python, and more
just download it from below link
https://www.visualstudio.com/en-us/products/visual-studio-community-vs.aspx
Thanks
Koolprasd2003
Editor, DotNetSpider MVM
Microsoft MVP 2014 [ASP.NET/IIS]