Usually in the back of your computer there is a panel with all the entries that it can receive and in there you'll find the audio board entries. You will also find FireWire, USB, PS2, parallel entries and maybe some other ones but in this section we're dealing exclusively with audio recording.

The audio entries are very easy to spot because they use a color pattern: Rose is the microphone entry, Green is the Line-Out, and Blue is the Line-In.

External audio devices such as LP's, cassettes, tapes, minidisks or other sound carriers will have to be plugged into Line-In, the Blue plug-in.

P2 is the connector that you will need to use to plug devices into your PC. If the device you're trying to plug in doesn't provide this type of cable you can easily find a cable that makes the bridge between your connector and P2. Cables with the right plugs on each end are sold at any appliance store for a couple of bucks.

You can use 1AVCenter to digitize music on LP's, cassettes, tapes, minidisks or other sound carriers, being played back on a regular home audio set, cassette player, minidisk player or tape deck for example.

To record from either one of these sound carriers, you have to connect the audio output of the player to the audio input of the computer.

What the audio output connection type on the player is, depends on the kind and model of the player.
It is usually marked Play-Out, Line-Out, Audio-Out or something in similar wording DIN connectors, RCA connectors, Mini-jack connectors

To record from vinyl records, you will need a (pre-)amplifier connected in between the turntable and the computer.
The signal strength of the turntable output is most times too weak to be connected to the computer directly.
This is the same as when you record LP's to tape on a tape or cassette deck for example.
Your home audio set will have a pre-amp built-in, if it has a Phono input and a Rec-Out output, connect the Rec-Out output to the Line-In input of your PC.