Cloudflare
Edge network and platform services: DNS, CDN, security, and serverless compute at the edge (Workers) among other products.
What it is
Cloudflare fronts your traffic for speed and filtering, and offers developer platforms to run code close to users. Product names span many layers (DNS, WAF, R2 storage, Workers, etc.).
Why it matters
It can reduce latency, absorb attack traffic, and host lightweight APIs or static assets globally without you operating regional servers manually.
When to use it
Use it when you need CDN/DNS, edge logic, or their storage and tunnel products fit your architecture. Map product to need. Cloudflare is a broad vendor, not one knob.
How it fits in the stack
Typically sits in front of or beside your origin: network and edge compute, not your primary database unless you adopt their data products intentionally.
Common confusion
Cloudflare is not a full replacement for your entire backend by default. Workers are not unlimited long-running servers; DNS changes are not instant everywhere. Read the specific product you enable.