: 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.

If you are joining multiple clips, they ideally should have the same resolution and aspect ratio for the best final look. Merge MP4 Videos: Combine MP4 Files for Free Online - Adobe

: Tap on the videos you want to merge, select the "Edit" or three-dot menu, and look for a "Create" or "Movie" option. This allows you to arrange multiple clips on a mobile timeline and add music.

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

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)

: Search for "Video Editor" or "Photos" in your search bar. Start a "New video project," add your MP4 files to the library, and drag them into the storyboard to arrange them.

: You can create a blank project, upload your clips, and drag them onto individual pages on a timeline to string them together.

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