The Encyclopedia of Mathematics (also EOM and formerly Encyclopaedia of Mathematics) is a large reference work in mathematics. It is available in book form and on CD-ROM.

The 2002 version contains more than 8,000 entries covering most areas of mathematics at a graduate level, and the presentation is technical in nature. The encyclopedia is edited by Michiel Hazewinkel and was published by Kluwer Academic Publishers until 2003, when Kluwer became part of Springer. The CD-ROM contains animations and three-dimensional objects.

The encyclopedia has been translated from the Soviet "Matematicheskaya entsiklopediya" (1977) originally edited by Ivan Matveevich Vinogradov and extended with comments and three supplements adding several thousand articles.

Until November 29, 2011, a static version of the encyclopedia could be browsed online free of charge online This URL now redirects to the new wiki incarnation of the EOM.

A new dynamic version of the encyclopedia is now available as a public wiki online. This new wiki is a collaboration between Springer and the European Mathematical Society. This new version of the encyclopedia includes the entire contents of the previous online version, but all entries can now be publicly updated to include the newest advancements in mathematics. All entries will be monitored for content accuracy by members of an editorial board selected by the European Mathematical Society.

1. What EOM stands for?
2. What is it?
3. In how many formats it is available?
4. What are they?
5. Was a static version available?
6. Was it discontinued?
7. When?
8. Was it free?
9. What is the new version now?
10. How many organizations work together to make it possible?
11. What are they?
12. Can this be edited by public?
13. How many entries were there in 2002?
14. Is the presentation technical?
15. Who was the editor?
16. And publisher?
17. Until when?
18. Then what organizational change happened?
19. What the CD contains?
20. Who select the editorial board?

Numbered answers:
1. Encyclopedia of Mathematics
2. a reference work in mathematics.
3. Two
4. book and CD-RoM
5. yes
6. yes
7. November 29, 2011
8. yes
9. a public wiki online.
10. Two
11. Springer and the European Mathematical Society.
12. yes
13. more than 8,000
14. yes
15. Michiel Hazewinkel
16. Kluwer Academic Publishers
17. 2003
18. Kluwer became part of Springer
19. animations and three-dimensional objects
20. the European Mathematical Society.