How do I open or install LibreOffice?

I have downloaded LibriOffice but when I try to open it verifies but never opens. It appears in my applications and a copy on my desktop but neither application will open. I have Mac OS X Yosemite 10.10.5
I’m not finding any installation information because it won’t open.

@mpoague: Welcome to the forum! Please do not check the community wiki checkbox. Also, a tag such as installation would make more sense than common. See guidelines for asking. Glad to see you’ve included operating system information. Please also include what LO version you downloaded, including whether it’s 64-bit. If you tried version 6, then see if the older version 5 works instead.

Thank you so much for answering. I’m sorry I didn’t understand the tag thing. I have never used an online help service. I downloaded 6 64-bit. I will try 5 64-bit. Do I need to uninstall the 6 64-bit?

5 is doing the same thing. It verifies but doesn’t open. Do you have any other ideas?

Check that your firewall/antivirus is not blocking it. Especially if it has a ransomware component.

Fire wall is off. Still won’t open. Any other ideas?