An antivirus program is a software application designed to detect, prevent, and remove malicious software (viruses, malware, etc.) from a computer system. Its primary function is to safeguard the computer's data and ensure its stability.

Antivirus programs protect a computer by:

• Scanning files and directories for known malicious signatures.
• Monitoring system activity for suspicious behavior.
• Blocking access to malicious websites and downloads.
• Removing or quarantining infected files.

Antivirus software employs several detection methods:

1. Signature-based detection: This method compares files against a database of known virus signatures. If a match is found, the file is flagged as malicious.
2. Heuristic analysis: This method analyzes the code of a file for suspicious behavior, even if the file is not in the signature database. It looks for characteristics commonly associated with malware, such as attempts to modify system files or access sensitive data.
3. Behavioral monitoring: This method monitors the actions of programs running on the computer. If a program exhibits suspicious behavior (e.g., attempting to modify system files, connecting to unknown network addresses), it is flagged as potentially malicious.

The primary purpose of encryption in protecting data transmitted over the internet is to ensure confidentiality, integrity, and authentication. Confidentiality means preventing unauthorized access to the data. Integrity ensures the data hasn't been altered during transmission. Authentication verifies the identity of the sender.

Symmetric encryption uses the same key for encryption and decryption. It's generally faster than asymmetric encryption. A real-world example is encrypting a file on a local computer using AES. It's efficient for encrypting large amounts of data when a secure channel already exists.

Asymmetric encryption uses a pair of keys – a public key for encryption and a private key for decryption. It's slower than symmetric encryption but provides stronger security. A real-world example is using HTTPS on a website. The website's public key is used to encrypt the session key, which is then used for symmetric encryption of the data transmitted between the browser and the server. This allows secure communication even if the private key isn't known.

A school collecting student data has several legal and ethical obligations. Two important requirements are:

1. Compliance with GDPR (General Data Protection Regulation) or relevant data protection laws: GDPR sets out rules about how personal data must be collected, stored, and used. Schools must obtain explicit consent from parents or guardians before collecting and processing sensitive data like medical information. They must also ensure that the data is stored securely and that appropriate measures are in place to prevent data breaches. This is important because it protects the rights of students and ensures that their data is handled responsibly and ethically. Failure to comply can result in significant fines and reputational damage.
2. Data Minimisation: The school should only collect data that is necessary for legitimate purposes, such as providing education and ensuring student well-being. Collecting excessive or irrelevant data increases the risk of data breaches and misuse. By limiting the amount of data collected, the school reduces the potential harm that could result from a data breach. This is important for respecting student privacy and avoiding unnecessary risks.