what is virus in computer

A computer virus is a type of malware that can replicate itself by modifying other computer programs and inserting its own code into those programs. Once the virus has infected a program, it can spread to other computers and cause damage to data and software. Computer viruses can infect a variety of different subsystems on their host computers and software, including binary executables, data files, or the boot sector of the hosts hard drive. Some viruses are harmless, while others may damage data files, corrupt data, or steal private information such as credit card numbers, debit card numbers, phone numbers, names, email addresses, passwords, bank information, and house addresses. Viruses can be spread via email, infected email attachments, networks, drives, file-sharing programs, or infected code repositories. Unlike worms, viruses often require some sort of user action, such as opening an email attachment or visiting a malicious web page, to spread. To protect against viruses, it is recommended to install anti-virus software, which can identify and block many viruses before they can infect your computer.