src and href

The href is a link to the location of the network resource, the establishment and the current element (anchor point), or the current document (link), for hyperlinks.

src is the location of the external resource, which is embedded in the document where the current label is located, and the resource it points to is downloaded and applied to the document when the SRC resource is requested, such as JS scripts, IMG images, and other elements. When the browser resolves to the element, it pauses the download and processing of other resources until the resource is loaded, compiled, executed, and so on, like pictures and frames, similar to embedding the resource in the current tag.

src and href