Security headers every small business website needs
Six HTTP security headers that close common gaps on business websites: what each does, safe starting values, and how to add them without breaking anything.
Posts about Website security
2 guides on this topic.
SPF, DKIM and DMARC explained for small business owners
What SPF, DKIM and DMARC actually do, how they work together to stop people faking your email address, and a safe step-by-step way to set them up.