SlackSlack

Slack Usage Statistics · Download List of All Websites using Slack

Messaging app for teams that makes working together simple and efficient.

Email Hosting Providers

SendgridSendgrid

Sendgrid Usage Statistics · Download List of All Websites using Sendgrid

SendGrid's cloud-based email infrastructure provides businesses with email delivery management.

Transactional Email

SPFSPF

SPF Usage Statistics · Download List of All Websites using SPF

The Sender Policy Framework is an open standard specifying a technical method to prevent sender address forgery.

SSL Certificates

HSTSHSTS

HSTS Usage Statistics · Download List of All Websites using HSTS

Forces browsers to only communicate with the site using HTTPS.

HSTS IncludeSubdomains PreLoadHSTS IncludeSubdomains PreLoad

HSTS IncludeSubdomains PreLoad Usage Statistics · Download List of All Websites using HSTS IncludeSubdomains PreLoad

This website includes instructions for HSTS loading that would allow it to be submitted to the HSTS preload list.

Operating Systems and Servers

OpenSSLOpenSSL

OpenSSL Usage Statistics · Download List of All Websites using OpenSSL

The OpenSSL Project is a collaborative effort to develop a robust, commercial-grade, full-featured, and Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols as well as a full-strength general purpose cryptography library.

UnixUnix

Unix Usage Statistics · Download List of All Websites using Unix

A *nix based operating system (undisclosed).

Web Servers

ApacheApache

Apache Usage Statistics · Download List of All Websites using Apache

Apache has been the most popular web server on the Internet since April 1996.