We get a lot of questions about what embeds to use where and when. We thought we'd help clarify what the differences are between our different embed types.
A Brief History of Embeds
We started with a dream. A dream of a terrifying Frankenstein embed that was actually more of a nightmare -- it turns out the idea of combining all of the embed types below into one freak being wasn't so plausible IRL. We then moved on to IFrames, but SEO was sort of inconsistent. In the end, it made the most sense to offer multiple embed options for different situations and priorities.
IFrames are sometimes the subject of unwarranted flack, with the mere word "frame" sending shivers of fear down the spines of those for whom it hearkens back to the illustrious frames of 1998 that basically served as a poor man's server side include. Now that most websites are built in dynamic languages, frames are obsolete. However, that "I" makes all the difference, and IFrames are actually a super different and super useful tool that serves a completely different purpose.
If you're doing something basic without a ton of bells and whistles or embedding video in a third-party CMS, IFrames are the way to go.
If you need to add extraordinary features to your video embeds, API embeds are for you.
SEO embeds use old object tags so they're crawlable by those creepy search engine robots that make you Internet famous. SEO is inconsistent with IFrames; Google's official stance is that they don't crawl IFrames, although sometimes things like an image still or link might sneak their way in. These also use noscript tags to make sure transcripts are visible to everyone. However, they lack the universal compatibility of IFrames.
If SEO is a priority then use SEO embeds.
The obvious benefit to popover embeds is that they free up page real estate while allowing those who want to view your video to view it at a resolution that doesn't require a magnifying glass. That aside, since they use an IFrame, they also basically share all of the other benefits of IFrame embeds.
If you don't have a lot of space for a video on your page, use popovers.