Microsoft, do provide downloadable .NET framework software through their official website Download section but most of them are online installer that means you will be given an online Microsoft .NET framework installer software of a given size less than 4mb or so and then after install that it will start downloading .NET framework files through it. This option is best for those who have better connectivity and their internet does not get disconnect for a while.
But if have 2G connectivity , Slow speed internet or simply want to save your internet Bandwidth then you can download directly standalone installer of Microsoft .NET framework various version
Microsoft .NET Framework 4 Client Profile (Standalone Installer)
Microsoft .NET Framework Client Profile Offline Installer
- Download setup
Microsoft .NET Framework 4.5
Microsoft .NET Framework 4 (Standalone Installer)
Microsoft .NET Framework 3.5 Service Pack 1 Full Package
Microsoft .NET Framework 3.5 Setup
Service Pack 2 for Microsoft .NET Framework 2.0
Microsoft .NET Framework 2.0 Service Pack 1 (x86)
- Download 32-bit
Microsoft .NET Framework Version 2.0 Redistributable Package (x64)
- Download 64-bit
Notes- If you have downloaded the latest version of .NET framework version in your computer then there is no need to install the previous/earlier version because in the latest framework all the old features of previous .net frameworks are already included in it.