How to use this glossary
Each term has a plain definition, where you meet it in common editors, and what to do with it. Definitions lean on the Kdenlive manual, which publishes an open glossary, and on vendor help pages for where a feature lives. Menu names change between versions, so treat the locations as a starting point. [1][2]
Timeline and structure
| Term | Plain meaning | Where you meet it |
|---|---|---|
| Timeline | The main editing area where clips are arranged in time across tracks | Every editor; Kdenlive calls it the central part of the app [1] |
| Track | A row on the timeline that holds clips; can usually be muted or locked | Track headers, where Kdenlive lets you mute, lock or resize a track [1] |
| Clip | Any piece of video, audio, still image or generated item, such as a title, placed in a project | Media bin and timeline [1] |
| Playhead | The vertical line marking the current frame; many commands act at the playhead | Cut at playhead shortcuts, keyframe placement [2][5] |
| Sequence or nested timeline | A separate timeline inside the same project; Kdenlive describes a sequence as basically a timeline | Kdenlive added sequences in version 23.04.0 [1] |
| Aspect ratio | Frame shape, such as 16:9 horizontal, 9:16 vertical or 1:1 square | Project or composition settings; Descript offers Landscape, Square, Portrait or Other [10] |
Cutting and trimming
What to do: turn on ripple behavior while assembling a rough cut, and turn it off once music and B-roll are aligned, because rippling later can push everything after the edit out of sync. Check which mode is on before deleting.
| Term | Plain meaning | Where you meet it |
|---|---|---|
| Split, razor or cut | Divide one clip into two at a point | Kdenlive's razor tool, or Shift+R to cut at the playhead [2] |
| Trim | Shorten a clip by moving its start or end | Drag a clip edge in any editor [2] |
| Ripple delete | Remove a clip or gap and slide everything after it left so no gap remains | Kdenlive [2]; Filmora right-click Ripple Delete or Shift+Delete [3] |
| Auto ripple | A mode that closes gaps automatically | Filmora Windows: Open Auto Ripple in the track panel [3] |
| Ripple tool | Trim a clip and shift the following clips by the same amount | Kdenlive edit tools [2] |
| Slip | Change which part of the source a clip shows, keeping its length and position | Kdenlive slip tool [2] |
| Insert versus overwrite | Insert pushes later clips right to make room; overwrite replaces what is underneath | Kdenlive timeline modes [2] |
| Jump cut | A visible jump where frames were removed from one continuous shot | Talking-head edits; Descript can smooth them with Regenerate using AI credits [9] |
Performance: proxy and render
Proxies do not lower your final quality: Filmora says the original media is used when you export. [4] Use them when 4K footage stutters on your computer. Filmora turns a rendered section red again once you edit it, so it has to be rendered again; render previews last, just before review. [6]
| Term | Plain meaning | Where you meet it |
|---|---|---|
| Proxy | A smaller, lower-quality copy of a clip used for smooth playback while editing | Filmora: Preferences, Performance, or right-click Create Proxy File [4]; Kdenlive Make proxy clip [1] |
| Render (export) | Turning the edited timeline into one finished video file | Export or Render dialog [1] |
| Preview render | Temporary files that let heavy sections play smoothly; not the final export | Filmora: red line over the timeline means unrendered, File, Render Preview turns it green [6] |
| Background render | Preview rendering that runs automatically when you pause | Filmora: Preferences, Performance, Background Render [6] |
Motion and look
| Term | Plain meaning | Where you meet it |
|---|---|---|
| Keyframe | A marker of an effect's value at a point in time; the editor fills in the change between two keyframes | Filmora keyframes scale, position, rotation, flip and opacity [5]; CapCut desktop lists keyframes and graphs [11] |
| B-roll | Secondary footage laid over the main shot, such as screen captures over a talking head | A layer above the main track; Descript's Replace Media swaps a B-roll clip in place [12] |
| LUT | A lookup table file that remaps colors to apply a grade in one step | FlexClip accepts LUTs in .cube format [8] |
| Transition | A dissolve or wipe between two overlapping clips | Transitions panel; Kdenlive treats it as a composition [1] |
Files and delivery
A practical default for YouTube from Google's own recommendations: MP4 container, H.264 video, AAC audio at 48 kHz, variable bitrate, and the frame rate you recorded at. For 4K at 24 to 30 fps, YouTube's recommended range is 35 to 45 Mbps. [7]
| Term | Plain meaning | Where you meet it |
|---|---|---|
| Codec | The method that compresses and decompresses video, such as H.264 or ProRes | Export format menus [1] |
| Container | The file type that wraps several compressed streams, such as video and audio, in one file, for example MP4 or MKV; not the same as a codec | The file extension [1] |
| Bitrate | How much data per second the video gets; more bits usually means fewer artifacts and a bigger file | Export settings; YouTube recommends about 8 Mbps for 1080p at 24-30 fps [7] |
| Frame rate (fps) | Images shown per second | Project and export settings; YouTube says export at the rate you recorded [7] |
| Resolution | Pixel dimensions, such as 1920x1080 (1080p) or 3840x2160 (4K) | Export settings; often capped by plan, for example CapCut desktop locks 4K and 60 fps for non-Pro users [13] |
First-month checklist
- Set project frame rate and aspect ratio before the first cut, to match your footage and platform. [7][10]
- Learn three shortcuts: split at playhead, ripple delete and undo.
- Turn on proxies if playback stutters; export still uses the originals. [4]
- Use keyframes for one simple move, such as a slow zoom, before trying graphs. [5]
- Export a 30-second test with your chosen codec, container and bitrate and watch it on the target device before exporting the full video. [7]
Questions before you decide
What is the difference between delete and ripple delete?
A plain delete leaves a gap where the clip was. Ripple delete removes the clip and slides everything after it left to fill the gap; Kdenlive and Filmora both document it, and Filmora maps it to Shift+Delete.
Do proxy files reduce my final export quality?
No. Filmora says proxies are smaller copies used for editing and that the editor uses the original media for the final export.
Is MP4 a codec?
No. Kdenlive's glossary defines MP4 and MKV as containers that wrap compressed streams, and H.264 or ProRes as codecs that do the compressing. YouTube recommends H.264 video inside an MP4 container.
What bitrate should I export 1080p video at for YouTube?
YouTube recommends about 8 Mbps for 1080p at 24, 25 or 30 fps and 12 Mbps at 48, 50 or 60 fps for SDR uploads, and says no bitrate limit is required.
Sources & verification
Product details and prices can change. Check the linked provider before buying.
- Kdenlive Documentation: Glossary Accessed 30 Oct 2026
- Kdenlive Documentation: Editing Accessed 30 Oct 2026
- Filmora Guide: Auto Ripple Accessed 30 Oct 2026
- Filmora Guide: Proxy video editing Accessed 30 Oct 2026
- Filmora Guide: Animation keyframing Accessed 30 Oct 2026
- Filmora Guide: Preview render files Accessed 30 Oct 2026
- YouTube Help: Recommended upload encoding settings Accessed 30 Oct 2026
- FlexClip Help: Supported video, audio, image, font, subtitle and LUT file formats Accessed 30 Oct 2026
- Descript Help: Smooth jump cuts Accessed 30 Oct 2026
- Descript Help: Aspect ratio and video settings Accessed 30 Oct 2026
- CapCut: Desktop video editor Accessed 30 Oct 2026
- Descript Help: Replace media Accessed 30 Oct 2026
- CapCut Help: Join CapCut Pro for exporting Accessed 30 Oct 2026
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