What does this mean?

It allows you to collect videos to save to boards. You can name the boards such as music, food, or exercises. They allow you to make them private or public.

If you are asking about the stylised character / icon above the Share arrow, it's a 好 character meaning good.

Consist of 女 (female) and 子 (child / boy / male), joined together in the stylised icon.

It's a bit different to the star, which is to collect videos (like saving on tiktok). 好 means good in Chinese and if you click it you're basically saying the vid is good, as if you are liking it. The only difference is that if you come across a video that your friend has watched, you can see if they have clicked this button, it will usually come up with something like "xxx觉得好" (xxx thinks this is good).

it means your post got “picked” — kinda like a featured or boosted post. it’s different from likes or saves. it helps push your content further. basically: nice job 🎯

People click on this to recommend this information to more people.