Yes, a green screen is often used in the production of YouTube videos, but it is not always required. A green screen, also known as a chroma key, is a backdrop that is a bright green color and is used to replace the background of a video with a different image or video footage during post-production.
While green screens are commonly used by YouTubers to create visually appealing videos, they are not necessary for all types of content. For example, a vlogger who simply speaks to the camera about their day-to-day life may not need a green screen. However, creators who make videos with special effects, like science fiction or action scenes, or those who want to create an immersive environment for their audience, may find a green screen to be a useful tool.
In addition to a green screen, other tools and techniques can be used to create similar effects. For instance, practical effects, like physical props and sets, can be used to create a realistic environment without the need for a green screen. In some cases, digital effects can be created without the use of a green screen by carefully selecting and isolating the subject or object in the footage.
When it comes to deciding whether to use a green screen for a YouTube video, creators should consider their specific needs and the type of content they want to create. It's also important to keep in mind that using a green screen can be time-consuming and requires some technical knowledge, so it may not be feasible for all creators. Ultimately, the decision to use a green screen or not will depend on the goals of the video and the resources available to the creator.