If you download a file from the internet, you can't always be 100% sure that the file has not been altered from its original state by a malicious party. This could occur either while the file was being hosted (someone changed it) or on it's way to you, if the attacker makes your computer think it's downloading it from the original source.
One of the standardized ways you can determine if a file has been changed from its original state or not is to check the files integrity by looking at its hash value (it's digital fingerprint). Each and every different file has unique data contained within it. When you apply a certain algorithm called a “cryptographic hash function” (in this case SHA1) to it, a string value is returned which is only valid for that file in its current state. If any of the data in the file is altered, even 1 byte, and you check the algorithm again, the string value/hash outputted this time will be completely different from the first value. With this information, you can tell if the file is exactly the same you are intending to download before you try to use it.
Below are simple ways you can verify the checksums on three desktop platforms where the Jaxx Wallet App is supported. You can double-check the Jaxx Wallet app to see if the hashes match after you download them and before you install them.
We always post the hash values of the downloadable Jaxx Wallet installers on our website and can be viewed after selecting the preferred Desktop platform to download on our website: https://jaxx.io/downloads.html
How to get a file's checksum:
WINDOWS:
1. Open "Command Prompt".
2. Type "certutil -hashfile"
3. Drag & Drop the file into the Command prompt window.
4. Type "sha1"
5. Press "Enter"
6. The hash will be displayed for you to validate.
OSX and Linux:
1. Open "Terminal".
2. Type "sha1sum".
3. Drag & Drop the file onto the terminal window.
(How to drop and drag: https://en.wikipedia.org/wiki/Drag_and_drop)
4. Press "Enter".
5. The hash will be displayed for you to validate.