Physical Media

CD/DVD

A CD (Compact Disc) and DVD (Digital Versatile Disc) are optical discs that store digital data. CDs typically hold up to 700 MB of data and were widely used to distribute music and software. DVDs hold considerably more — up to around 4.7 GB on a single-layer disc — making them the standard format for distributing films, games, and large software packages throughout the late 1990s and 2000s.

Advantages include being a relatively cheap medium to produce in bulk, making them economical for large-scale distribution. Physical discs give the audience something to own permanently, and they do not require an internet connection to use once purchased. They also have a defined storage capacity, which means the product is delivered as a complete, finished item.

Disadvantages include fragility — discs can be scratched or cracked, rendering them unreadable. They also have a fixed storage limit, meaning they cannot be updated or amended once pressed. Perhaps most significantly, optical disc drives are increasingly rare in modern computers and laptops, which limits the audience that can actually use them. Blu-ray discs offer greater storage capacity and are used for high-definition film, but the same compatibility concerns apply.

Because content on a CD or DVD is stored locally and played back on capable hardware, a range of file formats can be used. Video is typically stored as MPEG-2 on DVDs; audio CDs use uncompressed WAV or AIFF formats. The fixed capacity of the disc does, however, mean that large uncompressed files may need careful management to fit within the storage limit.