Facebook

Facebook remains the largest social network by user count, and while its cultural centre of gravity has shifted to younger platforms, its reach in many markets is still unmatched — particularly outside North America and Western Europe.

For businesses its practical value is less the feed than the surrounding infrastructure: Pages, Groups, Marketplace, and an advertising system whose targeting and measurement remain among the most developed available.

Organic reach for Pages has declined steadily for years, so treating it as a free distribution channel usually disappoints. It works better as a paid acquisition platform combined with Groups for retention.