Q: OS 10.10.0

Upgrade to El Capitan if your device is compatible. How old is your Mac?

Upgrade to OS X El Capitan - Apple Support

You are welcome. If your device has at least 2 gb of RAM and 8.8gb of free space it is ok.

You are welcome once again =).

make sure software installed on your Mac is fully compatible with El Capitan and back up important data.

The system requirements for Mountain Lion and later are identical. Thus since the OP has Mavericks it meets the requirements for El Capitan too.

thunderzzz wrote:

 

Upgrade to El Capitan if your device is compatible. How old is your Mac?

Upgrade to OS X El Capitan - Apple Support

You'd better read this short article just in case.

http://osxdaily.com/2015/09/29/prepare-mac-os-x-el-capitan/

Use Time Machine to create a backup.

Use Time Machine to back up or restore your Mac - Apple Support

Then upgrade to OS X El Capitan version 10.11.4

Upgrade to OS X El Capitan - Apple Support

If there's any issues after upgrading, Time Machine can be used to restore back to 10.9.5 with all our data at the time the backup was created.  Some apps may not have been updated by the app developers and may not function under El Capitan.