Recording directly basically involves plugging into any sort of interface or desktop unit that gets your guitar into the computer using a USB or Firewire cable.
From then on in, many things such as speaker simulation, amp modeling, eq’s, effects, compressors is entirely software based in any sort of audio program.
By plugging straight into an interface unit, you are removing the need to use an amplifier, and are therefore recording the guitar clean. Recording the guitar clean enables you to add effects later with plug-ins making it easy to edit, and chop and change. Programs such as Cubase and Sonar offer any fantastic plug-ins that are very convincing to the ear.
You may have seen guides explaining how you can plug your guitar directly into your standard soundcard using a jack plug and connector. Whilst this will enable you to hear your guitar through your speakers, the sound is very quiet, and is completely unsuitable for any kind of recording.
By using an interface or desktop unit such as the M-Audio FireWire Solo for instance, you’ll be eliminating the need to use your standard sound card. Using an interface unit couldn’t be more simple; it is really is a case of just plugging in your guitar.
The recording interface unit will then send the sound to your computer via a USB or FireWire cable, depending on which type of port/connector you have.
There are a wide variety of interfaces available, ranging in both price and quality. With a little reading you should find a product that suits your needs and budget in no time. As always, make sure you shop around to find the best deal. Several websites now allow users to add their own reviews after they have purchased a product, always pay attention as those customers have first hand experience.