What does a network interface card (NIC) do?

A network interface card (NIC) is a hardware component that allows a computer to connect to a network, facilitating communication between the computer and the network. It acts as an interface, providing a means for the computer to send and receive data over a network, whether that network is wired or wireless. The NIC communicates with the network using various protocols and ensures that data is transmitted and received correctly.

In this role, the NIC plays a crucial part in network connectivity by transforming digital data from the computer into the format suitable for transmission over the network and vice versa. It manages the connection to the network’s infrastructure, enabling effective communication with other devices, routers, and servers.

Other options describe important aspects of networking, but they do not accurately define the primary function of a NIC. Connecting computers directly to the internet may involve a NIC, but the NIC itself is about network communication rather than direct internet access. Increasing network speed can be influenced by various factors like bandwidth and hardware capabilities, but the NIC's primary role is not speed enhancement. Filtering malicious data packets generally pertains to security measures like firewalls and intrusion detection systems, which are separate components of a network architecture.