“发表” is almost exclusively used in formal or semi-formal contexts. You will encounter it frequently in academia, business, government, and media.
Academic and Literary Contexts: This is the most common usage. It refers to the publication of research, articles, and creative works.
Formal Speeches and Opinions: Used when someone is officially presenting their views.
`发表讲话` (fābiǎo jiǎnghuà) - to deliver a speech
`发表意见` (fābiǎo yìjiàn) - to express/state an opinion (in a meeting, forum, etc.)
Official Announcements: Governments and organizations use it to issue official communications.
Online Content: While `分享 (fēnxiǎng)` (to share) is more common for casual social media posts, “发表” can be used for more substantial online content like a detailed blog post or a formal online article.