: A straightforward drag-and-drop tool that supports adding crossfade transitions between clips and handles different aspect ratios. Desktop Software (Built-in or Free)

: A professional-grade free option for PC or Mac if you want advanced editing features like color grading and complex transitions.

: Allows you to upload multiple MP4 files (up to 1 hour each) and use a trim tool to control cuts before downloading the merged result.

: Open iMovie, start a new "Movie" project, and select the clips from your library. You can then tap "Create Movie" to join them instantly.

These are ideal for simple merging without downloading software:

To "put together a piece" using video files like 0guqd3oqmm0rliy2v2qjp_source.mp4 , you can use various free tools and methods depending on your device and desired complexity. Online Tools (Quickest & No Install)