FoldersSynchronizer is a nifty and popular utility for Macintosh (Classic and Mac OS X Jaguar, Panther, Tiger and Leopard) which synchronizes and backs-up files, folders and disks. The user can choose one or more pairs of files/folders/disks and then they will be synchronized/backed-up exactly. FoldersSynchronizer is available also as lite version.

When synchronizing, the old files will be replaced with the newest files in both directions. The new files (new entries) will be copied in both directions, as well as new Folders. The old Folders will not be replaced entirely by the newer ones, as the Finder used to do, but their content will be updated with the newest files, the new files (new entries) and new Folders (new entries).
FoldersSynchronizer can execute incremental or exact synchronizations. The incremental synchronization (default) never deletes items from the folders. The exact synchronization deletes from a folder, all the items no longer existing in the specular folder.

When backing up, the destination folder will be upgraded with the newest files, the new files (new entries) and the new Folders (new entries) coming from the source folder; the source folder will be left untouched.
FoldersSynchronizer can execute incremental or exact backups. The incremental backup (default) never deletes items. The exact backup deletes from the destination folder, all the items no longer existing in the source folder, and it never deletes items nested inside the source folder.

On each single session, FS can apply special options like Timer, Multiple Folders, Filters, Excluding Items List, Resolve Conflicts, Automount Local and Remote Volumes, Launch AppleScripts, Settings. Take a look at the Overview to know more about each single option.

Here the user can specify global settings like whether FS should make a preview listing all the files FS is going to copy, replace and delete. Also he can specify to save a log file, to send a log file to a custom email address, to sync and automatically quit the application, and more. Take a look at the Preferences page to know more.

• FS can backup the whole MacOS X boot disk and make it bootable.
• FS can automount volumes.
• FS can exactly sync and exact backup the files/folders deleted or renamed (Exact Sync and Exact Backup features).
• FS can create, save and open Sessions Files.
• FS allows creating, renaming, duplicating, deleting, editing of several Sessions in a single file.
• FS can assign to each session, source/destination folders, Settings, Timers, Multiple Folders, Filters, Exclude, Conflicts.
• FS can execute in a single task, one or all the Sessions defined in a file.
• FS can execute one or all the Sessions simultaneously at the time you specify in the timer list.
• FS can show the Timer Scheduling list.
• FS can execute Multiple synchronizations/backup (up to 32 pairs of folders) specified by a single Session.
• FS can Filter the documents to copy by FileName, Type, Creator, Creation Date, Modification Date and Kind (File or Folder).
• FS can Exclude from the sync or backup, the folders and files (with absolute path) you specify in the Excluding item list.
• FS can check and behave as you specify whether a Conflict occurred before replacing or deleting a recently updated file.
• FS can check whether both the files have been modified after the last Sync/Backup.
• FS can check, during a backup, whether the destination file has a most recent modification date.
• FS can run an user's AppleScript before and after executing each session (sync or backup).
• FS can copy invisible Files and Folders.
• FS can include/unlock the locked files, so it can delete/replace also the locked files, if necessary.
• FS can resolve Aliases and SYM links.
• FS can skip the empty folders.
• FS can copy the new files only and skip the most recently updated files.
• FS can stop or skip or ask for further instruction, if an error or a conflict occurs.
• FS can show the "Items to be copied" Preview List. Here, again, the user can select the items to be excluded (skip).
• FS can save/display short or detailed Log Files (always or only if an error occurred).
• FS can send the Log Text via Email to a custom email address (always or only if an error occurred).
• FS can work with root privileges, even if the user is not the root (if requested by the user, FS asks for the root's password at any launch).
• FS can use a "modification date delta seconds" value when calculating the most recent file.
• FS works properly on Unicode Strings, Long file names, Unix permissions, Multiple forks, Forks > 2GBytes, SYM links and GMT Date/Time.
• FS allows drag and drop of source and destination folders/files/disks and aliases.
• FS can work in background (multithreading).
• FS registered copies have no limits regarding the amount of files and folders or the total byte size.
• FS versions for MacOS Classic never needs extra memory for large amount of files too.
• FS has been tested successfully MacOS X from 10.1.2, to 10.4 (Tiger).
• Complete and detailed list of features, technical notes, requirements, version history, upgrade prices, ordering info, is at the Release Notes page.