I'm asking because I saw a few posts in my home feed that I can't verify. By the way, Lemmy can't be compared to Reddit if it doesn't have the ability to post videos or GIFs. Think about it: what good is a social media platform without the ability to share the most popular forms of multimedia?
No, but you can link to an external video. Unfortunately videos are very taxing on servers (and therefore expensive to deal with), so it's unlikely we'll see them in Lemmy in the near future.
It's up to the client on how to render them. Most videos I encounter in Lemmy are linked from outside sources or are on YouTube.
Lemmy-UI has no or limited support for anything but images.
Tesseract is on the other end of the spectrum and supports pretty much every kind of media.
Photon supports GIFs and native (mp4, webm) videos.
Other UIs and mobile apps, I haven't kept as up-to-date on but are typically somewhere between Lemmy-UI and Photon's level of media support.
Edit: In addition to what clients support, it's also up to each instance admin to define what media they allow to be uploaded. Among the possible configuration options are:
Whether to allow any media uploads at all
The max size of the media they'll allow users to upload
Whether to allow videos or just static images
Whether to convert videos to GIFs or static images
Whether the media subsystem (pict-rs) can process the upload before the upload request times out. I think that's 10 seconds which limits direct uploads to short videos.
Like others have said, hosting videos is expensive both in areas of storage and bandwidth. Most Lemmy instances are run by volunteers at their cost or operate solely on donations. Admins typically ask users to host those off-server (Imgur, YouTube, Catbox, etc) and restrict what can be uploaded directly to reasonable limits.
I wouldn't want Lemmy to host videos, they require a lot of storage and bandwidth for a service the users pay nothing for. 60 seconds of video could equal many thousands of text posts and links. I hope Lemmy stays simple.
I would like for some instances of lemmy in future to consider adding videos prehaps to save on server costs have the videos set to 480p or 720p max this will add an entirely new layer of content to lemmy prehaps said instances and supplement there income with ads and donations
I posted a .gif in a comment the other day just using the base lemmy.world interface on desktop and it Just Worked. I don't know about other clients/UI's.
I mostly screw off on lemmy while I'm supposed to be working, so I exclusively use the desktop interface in a browser. From what I understand, the different apps and interfaces don't all quite support displaying the same types of content or even markdown... yet. For instance, a I had another poster tell me that spoiler tags don't work in the Boost app.
I think you can upload just about any damn fool thing as an inline image and the server will take it; it's just a matter of the client being able to make heads or tails of what it is and display it appropriately.
Luckily hosting videos require quite a lot of resources so it will be too much for many smaller, selfhosted instances, which will hopefully contain the spread of it.