Online security refers to the measures taken to protect personal information and data while using the internet. This includes safeguarding against threats like hacking, phishing, and malware, which can compromise sensitive information such as passwords and financial details. To enhance online security, individuals can use strong passwords, enable two-factor authentication, and regularly update their software. Additionally, being cautious about sharing personal information on social media and recognizing suspicious emails can help prevent security breaches. Tools like antivirus software and firewalls also play a crucial role in maintaining a secure online environment.