All audio connectors are made via standard mini-Din. This is the standard type of connectors for your computer. If your speakers do not use these connectors, you'll need to purchase adapters, which are sold in any specialty store.
Port Line Out is a connector to which you want to connect external speakers. Remember that some monitors can be integrated with speakers. Standard connector is highlighted in green.
In connector Microphone – connects a microphone that allows users to record own voice or any other sounds. Typically, this port is highlighted in pink.
The Line In port is used to connect various external devices. For example, you can connect a VCR in order to play a sound at the speakers.