Free program to synchronize folder and files

Do you know how to synchronize folder and files on the same computer or online for backup or to update in different locations?
Synchronize means if you make the change in any file in one location the data will update same time in different folder or location. Synchronization is very useful for backup or updates purpose. Synchronization is also used to share the data with another user or to save in network attached storage device (NAS).
If you synchronize the date in the different location of the same computer or synchronizing in external or USB drive it is offline synchronization. Offline synchronization is useful for data safety or for backup purpose. There are many free and paid programs are available for data synchronization and for backup also. Now we are talking about synchronization of folders. Dsynchronize is one of best free software/ tool for folder sync. Dsynchronize a good programmed for real-time synchronizing two folders.
This programme has two boxes, one for source folder and one for the destination folder. We have to configure the folders first. This programme has filter facility to exclude any subfolder. This programme looks old but it is useful and reliable to real-time folder synchronize. Choose the Bidirectional synchronization to synch the folder in both directions. Checking Create folder option to enable the programme to create a new folder in the other synced folder if it does not exist.
Backup changes option will keep several versions of the changes
Enable the Real-time sync under special option for real-time synchronization. Under timer sync, check the autostart and autostart as service to start the sync automatically.

For online folder synchronization, many online services are available some powerful and free online cloud storage drive or folders are Google Drive, Dropbox, Skydrive, Pcloud these services are free and best for online storage and folder and file synchronization. You can use this from any computer through a browser for update the storage or if you want to synchronize the folder then you can download the windows version and install on your computer.
we hope that you like the programme please post the comment and share your experience.