You can use SMB protocol to transfer data over your WiFi network.  

If your computer shares folders on your WiFi network, you can then access these folders and copy or use their content. A shared folder on your device is represented by an icon with a hand holding a folder. To share a folder from your computer, click on the right mouse button and select "share and security" (for Windows® XP) / "share with…" (for Windows® 7 & 8). 

You can navigate through the shared folders by using the Files application  . In this app, select Network on the left and then Shared folders (SMB). The network name of your computer will appear, press it to see your shared folders.  Look for the file you want to transfer and then long press the file, select copy and navigate through the internal storage of your device (left panel) and paste the file in the desired folder.  

If the computer sharing folders runs Windows® and has an ID number and password to connect, you will need to provide this to access the content of the shared folders. 

Please note the transfer of large files over WiFi is not recommended.