Modern media consumption varies significantly by demographic: Media Consumption by Different Age Groups
The "517" designation is often a defensive measure against legal liabilities like COPPA (Children's Online Privacy Protection Act) in the US or the Online Safety Bill in the UK. By explicitly labeling content for 17+, website operators accomplish three things: 517 age porn website full
If “517” is a project name or brand (e.g., Section 517): Section 517): References (abridged)
References (abridged)