AVG AntiVirus - AVG AntiVirus has been protecting the computer systems of more than 200 million individuals since it was introduced.
Digicert - Encryption & Authentication
Windows Defender - Windows 10 security delivers built-in & ongoing protections you can trust: Windows Defender Antivirus, firewall, family settings, ransomware protection, real-time protection & more. Stay up to date & protected at no extra cost.
Comodo - Comodo, the leading Internet Security Provider offers Free Antivirus, SSL Certificate and other Internet Security related products with complete protection
Malwarebytes - Malwarebytes protects you against malware, ransomware, and other advanced online threats that have made antivirus obsolete and ineffective. Free Anti-Malware & Malware .
Let's Encrypt - Let’s Encrypt is a free, automated, and open certificate authority brought to you by the Internet Security Research Group (ISRG).