Obsolescence Ratings

How easy is it to find equipment to read information from different formats? What priority should be given to migration or preservation of media?

This list categorises the ease with which a range of formats that have been, or are, in common use in their fields can be read, in terms of the equipment available to do so. This may not always be by the original equipment; for example many turntables will play 78rpm records, and film scanning machines enable digitisation of motion picture film.

However, even for formats where equipment is easily available, there may still be separate issues of media stability and file format obsolescence to consider.

obsolescence 55. Extinct, or very high risk

Equipment capable of reading or transcribing the media may be very specialist, rare, or difficult or expensive to maintain.

Brown wax cylinder (late-1880s to 1906)

Wire recording (1898 – 1960s)

Dictabelt (1947 – 1980)

EIAJ-1 ½-inch open reel video tape (1969 – early 1980s)

8-inch floppy disk (1971 – early 1980s)

EIAJ-2 (1972 – late 1970s)

Video Cassette Recording (VCR) (1972 – 1979)

1-inch Type B (1975 – 1980s)

1-inch Type C (1976 – mid 1990s)

DASH (Digital Audio Stationary Head) (1982 – mid-1990s)

3.25-inch floppy disk (1983 – mid 1980s)

2.8-inch DataDisk (1986 – early 1990s)

MII (1986 – early 1990s)

obsolescence 44. Endangered, or high risk

Equipment capable of reading the media may be increasingly rare, or difficult or expensive to maintain.

Gold-Moulded Records (1902 – 1912)

Amberol Records (1908 – 1912)

Blue Amberol Records (1912 – 1929)

5.25-inch minifloppy disk (1976 – early 1990s)

U-matic (1973 – 1990s)

D2 (1988 – 2000s)

obsolescence 33. Threatened, or moderate risk

Equipment capable of reading the media may not be readily available, or may need to be carefully maintained.

Acetate / lacquer disc (late 1920s – )

¼-inch open reel tape (1949 – 1980s)

8-Track (Stereo 8) (1964 – 1988)

Betamax (1978 – 1988)

LaserDisc (1983 – 2001)

Video8 (1985 – 2000s)

Betacam SP (1986 – 2001)

Digital Audio Tape (DAT)  (1987 – 2005)

Digital Data Storage (DDS) (1989 – 2007)

Iomega Zip (1995 – 2003)

Iomega Jaz (1996 – 2002)

Betacam SX (1996 – 2007)

obsolescence 22. Vulnerable, or some risk

The format is no longer current but may still be in use, and equipment capable of reading the media is still relatively common even if no longer produced.

3.5-inch microfloppy disk (High Density) (1987 – late 2000s)

Compact Cassette (1963 – 2000s)

VHS (Video Home System) (1977 – late 2000s)

Hi8 (1989 – 2007)

MiniDisc (1992 – 2013)

MiniDV (1995 – late 2000s)

Digital 8 (1999 – 2007)

obsolescence 11. In current use, or low risk

Equipment capable of reading the media is still produced, or is still widely available (perhaps because of backwards compatibility, adaptors, or alternatives such as scanning of film negatives)

10-inch 78 rpm record (1901 – 1960)

16mm film (1923 – )

12-inch LP (1948 – )

7-inch single (1949 – )

Super 8 (1965 – )

Microcassette (1969 -)

Mini-Cassette (1967 -)

Compact Disc (1983 -)

CD-ROM (1985 – )

Compact Disc-Recordable (CD-R) (1992 – )

Digital Betacam (1993 – 2016)

CompactFlash (Type I) (1994 – )

DVCAM (1996 – )

Compact Disc-ReWritable (CD-RW) (1997 – )

DVD-ROM (1997 – )

DVD-R (1997 – )

Secure Digital (SD) (1999 – )

DVD-RW (1999 – )

USB flash drive (2000 – )

DVD+RW (2001 – )

DVD+R (2002 – )

Further considerations

The ratings are given from the perspective of the United Kingdom, and may vary greatly for some formats that were more, or less, widely available in certain markets. They are also highly subjective.

Sources / Resources