Libraries are a new feature in Final Cut Pro X version 10.1. A library contains both projects and events in one place. Think of libraries as a way to collect and organize related projects and events at a higher level. For example, you could use a separate library for each of your professional clients.  Or you could use libraries to separate different video productions, each of which contains its own projects and events.

Because a library contains both projects and events, it provides a single consolidated location for all your source media and edits. You can save libraries on any hard disk in any location. It’s easy to open and close libraries to access the media you need, and it’s simple to move media and projects between libraries.

When you first open Final Cut Pro X 10.1, you will see a window with three choices:

• Update All
This automatically updates all accessible projects and events and puts them in a separate library for each hard disk. Projects and events are accessible if they are in the Movies folder on your startup volume or at the root level of any mounted volumes. To be updated, projects and events must also be in the Final Cut Projects and Final Cut Events folders respectively.
• Update Later
This postpones updating. All of your existing content is unchanged and Final Cut Pro opens with a new empty library that contains no media. You can update your projects and events later by choosing File > Update Projects and Events.
• Locate
This lets you manually navigate to a connected hard disk, folder, or SAN location where projects and events are located for Final Cut Pro X to update them.

All of the projects that were in the Project library are collected in an event named Updated Projects at the top of the list of events in your new library in the Libraries list.

Media that you stored inside your original event is stored inside your new library. Media that was linked to an external folder and not copied inside your original event stays in that external folder and is linked to your new library.

Compound Clips and Multicam Clips are reference clips. When you modify a reference clip, the change is reflected in every instance of that clip.

When you update an event that contains instances of reference clips on other volumes, the reference clips are copied into the new library. The copies are independent of the original reference clips. This means that changes to the new reference clips don’t affect instances of the original clips.

No. It’s necessary to update all the projects and events within any Final Cut Projects or Final Cut Events folder at the same time so that references to assets, Compound Clips, and Multicam Clips can be properly resolved. You can also navigate to a SAN location on shared storage using the Locate command and update everything in that folder at once.

Click the Locate button when you first open Final Cut Pro X 10.1, or choose File > Update Projects and Events.

No. During the update process, Final Cut Pro creates links between the new Final Cut Pro 10.1 library and the media files in your old projects and events. If you delete your old project and event files, the media files remain in the new Final Cut Pro 10.1 library. If you delete the new Final Cut Pro 10.1 library, the media files remain in your old projects and events. By using these links, Final Cut Pro does not have to copy media files or use additional disk space.

Yes. When you successfully update your projects and events, the old projects and events are placed in a folder named “[Library Name] Old Final Cut Projects and Events,” next to the library file on the hard disk. You can choose to delete or archive these original files. Deleting these older project and event files after a successful update does not delete original media.

See Update your projects and events to Final Cut Pro 10.1

You can copy libraries between hard disks using the Finder.

Yes. However, it’s a good idea to use different names so that you can easily distinguish between libraries. If you use the same name for two libraries within the Final Cut Pro X application, the second library name is incremented (Library 1, Library 2, and so on) in the Libraries list. If you use the same name for two libraries in the Finder, both libraries appear with the same name in the Libraries list.

You can store libraries anywhere on your local file system, connected hard disks, or shared storage, including a storage area network (SAN) such as Xsan.

The new libraries created during the update process are labeled with the name of the volume or folder that contains the projects and events.

If your projects or events used Compound Clips or Multicam Clips from events on other volumes, the clips are created again in your new library. These files do not contain media and therefore take up very little space on your hard disks.

Libraries provide great flexibility for media management. You can create separate libraries for different productions or clients, or you can create a separate library for each of your events.

To create a new library, choose File > New Library. Copy an event to the new library by dragging it to the new library. You can also move an event to a library by choosing File > Copy to Library or File > Move to Library.

• See Update your projects and events to Final Cut Pro 10.1.
• For information about using libraries in Final Cut Pro X 10.1, see Managing Media with Final Cut Pro X Libraries.
• For comprehensive documentation on Final Cut Pro X 10.1, including instructions for organizing your libraries and media, see Final Cut Pro X Help at https://help.apple.com/finalcutpro.

This update improves overall stability, performance, and compatibility. Updates include:

• The Letterbox effect "Offset" slider is restored.
• Fixes an issue that could occur when creating a single layer DVD.
• Fixes an issue in which some third-party effects could cause Final Cut Pro to stop responding during background rendering.
• Fixes an issue in which some third-party transitions would incorrectly use black instead of source media.
• Adds support for editing MXF files that are still ingesting.
• Fixes an issue with rendering Motion Templates containing Image Units.
• Fixes an issue with the display of the Modify RED RAW settings button in synchronized and compound clips.
• Fixes an issue with the upload of clips that are larger than 1 GB to Vimeo.
• Fixes an issue in which an incorrect frame size is used with filters on two adjacent clips with different pixel aspect ratio.

Final Cut Pro X version 10.0.6 adds the following features:

• Expand multichannel audio files directly in the timeline for precise editing of individual audio channels.
• Unified import window provides single interface for transferring media from file-based cameras, networks, and folders of files. Choose between Filmstrip and List views for browsing media, and save frequently used locations to the Favorites sidebar for fast access.
• Redesigned Share interface for streamlined exporting. Deliver to multiple destinations in one step by creating a custom Bundle.
• Export a selected range in the Event Browser or the project timeline.
• RED camera support with native REDCODE RAW editing up to 5K and optional transcode to Apple ProRes 4444 or ProRes Proxy. Ability to adjust RAW images with debayer controls directly in Final Cut Pro.
• MXF plug-in support that allows you to work natively with MXF files from import through delivery using third-party plug-ins. This is ideal for importing archived media with custom metadata and exporting media with metadata to an asset management system.
• Dual viewers, each with a video scope display, let you compare shots to match action and color. Scopes include a vertical layout option so they can be displayed below the Viewer and the Event Viewer.
• Ability to add chapter markers in the timeline for export to video files, DVD, and Blu-ray disc, with an option for setting custom poster frames.
• Range selection now preserves start and end points on clips in the Event Browser. Use the Command key to create multiple range selections, even on a single clip.
• Paste attributes window lets you choose specific effects to copy between clips. 
• Flexible Clip Connections allow you to keep Connected Clips in place by pressing the ` key when slipping, sliding or moving clips in the Primary Storyline.
• Add a freeze frame to your timeline with a single keystroke (Option-F). 
• Apply a drop shadow effect with intuitive onscreen controls to adjust position, edge falloff, angle, and more. 
• Combine audio from different angles within a Multicam Clip (Command-Option-click in the Angle Viewer).
• Compound Clip creation in the timeline now saves the clip in the Event Browser for re-use in other projects. Changes to the original Compound Clip will update all copies of that Compound Clip across projects. The Reference New Parent Clip command allows you to select any Compound Clip in the timeline and save a duplicate to an event in a single step.
• XML 1.2 features improved metadata import and export for richer integration with third-party apps.
• Blade All command allows the blade tool to cut across all storylines and connected clips in a single click. Press Shift while blading to blade all. 
• Select a new default transition by Control-clicking on the thumbnail in the Transitions Browser and choosing Make Default. The default transition can be applied to any clip by pressing Command-T.

Final Cut Pro X version 10.0.6 improves overall stability and performance, and adds these fixes:

• Background Rendering uses the GPU on the graphics card, enabling CPU-based processes like transcoding and proxy creation to continue uninterrupted while effects are rendering.
• Loop Play with Play Selection enabled will continuously loop playback while making adjustments in the Inspector.
• DSLRs and other cameras that use the Picture Transfer Protocol (PTP) for data transfer will now appear in the Import window when directly connected to the computer.
• Improves system performance and smaller project sizes when working with Compound Clips.
• Clicking on a clip in the timeline selects the clip without moving the playhead. Option-clicking on a clip selects the clip and moves the playhead.
• Custom metadata views can be created and used as presets for exporting XML. Importing XML with custom metadata fields preserves data in Final Cut Pro.
• Ability to manually tag clips as anamorphic using the Anamorphic Override option in the Inspector.
• When duplicating an event or project where media resides on shared storage, only the links will be copied. This speeds up duplicating or moving events and projects to another editing station that is linked to the same shared media.
• Improves behavior when moving clips to different vertical positions in the timeline.
• Generators now support the 1.8:1 aspect ratio, which is used with a range of frame sizes.
• Video dissolves now default to the linear Video look instead of the Film look that includes some ease in and ease out.
• Ability to import SDII audio files.

Final Cut Pro X version 10.0.5 improves overall stability and is enhanced for the MacBook Pro (Retina, Mid 2012).

This update also addresses the following issues:

• Fixes an issue in which changes were not properly saved when working off a SAN.
• Improves performance when switching between projects on a SAN.
• Fixes an issue which could lead to Multicam Clips losing their Roles after relaunching Final Cut Pro X.
• Allows for YouTube uploads longer than 15 minutes.
• Correctly marks in and out points for spanned clips imported using the Sony Camera Import Plug-in PDZK-LT2.
   

Final Cut Pro X version 10.0.4 improves overall stability, performance, and compatibility including:

• Improves image quality and responsiveness of broadcast monitoring with compatible third-party PCIe and Thunderbolt I/O devices.
• Improves performance of multicam syncing and editing.
• Adds language support for Simplified Chinese.
• Adds a Share option for 1080p video on compatible iOS devices.

Final Cut Pro version 10.0.4 also addresses the following issues:

• Assigns default audio channel setting for new projects to stereo.
• Includes multicam metadata in XML project export.
• Fixes an issue in which video superimposed over a background with an alpha channel could appear differently in Viewer before and after render.
• Fixes an issue that caused some titles to be rendered again after each application launch.

Final Cut Pro X version 10.0.3 adds the following features:

• Multicam editing with automatic sync and support for mixed formats, mixed frame rates, and up to 64 camera angles
• Advanced chroma keying with controls for color sampling and edge quality
• Media relink for manual reconnect of projects and Events to new media
• Ability to import and edit layered Photoshop graphics
• XML 1.1 with support for primary color grades, effect parameters, and audio keyframes
• Multiple improvements to the Color Board, including new key commands, editable numeric fields, and adjustable parameters that act like infinite sliders when dragged
• Ability to reorder color corrections in the Inspector
• Reveal in Event Browser shows clip range in the filmstrip while in List View
• Batch offset for clip date and time
• Ability to search text added to Favorite and Reject ranges
• Beta version of broadcast monitoring with third-party PCIe and Thunderbolt I/O devices

Final Cut Pro X version 10.0.3 also improves overall stability and performance, and addresses the following issues:

• Improves performance when editing text in titles
• Improves performance when applying an effect from the Effect Browser
• Improves keyframing behavior in the Inspector, with keyframes automatically added when moving to a new point in time and adjusting a parameter
• Modifies transition behavior so that all newly added transitions use available media and maintain project length
• Fixes an issue which affected audio solo while skimming
• Resolves issues related to using Synchronize Clips with media containing a silent audio channel
• Fixes an issue in which constant speed retiming was not properly applied when using the Paste Effects command

This update is recommended for all users of Final Cut Pro X

• Fixes an issue in which a title may revert to the default font after restarting Final Cut Pro X
• Resolves an issue that could cause files recorded with certain third-party mobile devices to play back incorrectly
• Addresses a stability issue caused by changing the start time on a Compound Clip

This update is recommended for all users of Final Cut Pro X. For more information, visit www.apple.com/finalcutpro.

This update adds the following features:

• Export audio and video stems as a single multitrack QuickTime movie or as separate files using Roles
• Import and export XML to support third-party workflows
• Place Projects and Events on Xsan to improve collaboration between editors
• Set custom starting timecode for your projects
• Add transitions to connected clips in a single step
• Enable full-screen view in OS X Lion
• Speed up delivery with GPU-accelerated export
• Access the new Tribute theme, with four animated titles and a matching transition

This update also improves overall stability and performance, and addresses the following issues:

• Adds the ability to import DSLR video from Aperture and iPhoto libraries through the Photos Browser
• Adds the ability to eject camera cards while Final Cut Pro X is open
• Adds the ability to always use the startup volume or Time Machine volumes for media storage
• Improves audio syncing performance and ability to sync different frame sizes and frame rates
• Fixes an issue in which alpha channels in transitions were not properly preserved
• Resolves an issue that could cause titles to accidentally move in the timeline
• Improves the quality of video retiming when applying slow motion or when working with interlaced video
• Fixes an issue in which custom ICC color profiles affected the image in the Viewer
• Improves the performance and reliability of automatic saving