YouTube Channel Art, also called the YouTube banner, is the large art at the top of your channel page. When you visit a channel URL, you see some kind of image, or a field of gray triangles, which is the default art for people who haven’t placed anything there just yet.
Channel art is very free-form. You can upload just about anything, so long as the file size is under 6MB. YouTube recommends an image with the dimensions 2560×1440, which allows your image to look the best across different devices.
To preview a list of examples please visit Boostlikes.com