HomeGroupsTalkZeitgeist
This site uses cookies to deliver our services, improve performance, for analytics, and (if not signed in) for advertising. By using LibraryThing you acknowledge that you have read and understand our Terms of Service and Privacy Policy. Your use of the site and services is subject to these policies and terms.

Melvil Decimal System: 621.38220

Wording: Technology > Engineering > Mechanical Engineering and Machinery > Electric engineering > Electronics, Communications. > Communications > Not set > Not set

Dewmoji: πŸ’‘ > πŸ”© > 🏭 > ? > ? > ? > ? > ?

0
Information
196,074
ℹ️
1
Philosophy and Psychology
182,667
πŸ’­
2
Religion
462,730
πŸ™πŸ½
3
Social Sciences
1,016,516
πŸ‘«
4
Language
130,278
πŸ’¬
5
Mathematics and Science
322,754
πŸ”¬
6
Technology
751,392
πŸ’‘
7
Arts and Recreation
695,085
🎨
8
Literature
928,224
πŸ“š
9
Biography and History
591,421
πŸ—Ώ
60
General Technology
6,970
πŸ’‘
61
Medicine
251,858
πŸ’‰
62
Engineering
128,080
πŸ”©
63
Agriculture & Animal Husbandry
67,957
🌱
64
Home Economics
129,920
🏠
65
Business
119,838
πŸ‘”
66
Chemical Technology
15,659
πŸš€
67
Manufacturing
6,354
πŸ“¦
68
Handicraft and Occupations
15,500
πŸ”¨
69
Building
9,256
πŸ‘·
620
Engineering
18,950
πŸ”©
621
Mechanical Engineering and Machinery
40,539
🏭
622
Mining Engineering and Mines and Mineral Resources
2,832
πŸ•³
623
Military Engineering and Marine Engineering
11,891
βš“
624
Civil Engineering
7,076
πŸŒ‰
625
Road and Railroad
3,892
πŸ›€
626
--
35
🀷
627
Hydraulic Engineering
1,378
🌊
628
Sanitary; Municipal
6,166
🚽
629
Other Branches
35,321
🌿
621.0
1,010
621.1
Steam engineering
504
621.2
Hydraulic machinery
203
621.3
Electric engineering
28,314
621.4
Heat engineering
3,312
621.5
Pneumatic machinery and Compressed air and Refrigeration and refrigerating machinery
375
621.6
Fans (Machinery) and Pumping machinery
139
621.7
Production engineering and Factories and Machine-shop practice
129
621.8
Other mechanical engineering topics
2,179
621.9
Machine-tools
1,070
621.30
420
621.31
4,008
621.32
296
621.33
30
621.34
104
621.35
27
621.36
2,576
621.37
108
621.38
Electronics, Communications.
17,177
621.39
Computers
2,162
621.380
Light current engineering
262
621.381
Electronics
7,713
621.382
Communications
3,698
621.383
Telegrapy
24
621.384
Radar, Radio.
2,928
621.385
Telephony
268
621.386
Telephone terminal equipment
58
621.387
Telephone transmission equipment
21
621.388
Television
654
621.389
Audio, sound engineering
872
621.3820
77
621.3821
253
621.3822
663
621.3823
31
621.3824
126
621.3825
64
621.3826621.3827
214
621.3828
59
621.3829
621.38220
74
621.38221621.38222621.38223
45
621.38224
74
621.38225621.38226621.38227621.38228621.38229
621.382200
5
621.382201
34
621.382202
29
621.382203621.382204621.382205
1
621.382206621.382207
5
621.382208621.382209

Works under MDS 621.38220

1–50 of 71 ( next )titles | covers | shelf
( next )

Wording

1922 Edition
Modern language
Emoji

"Far Friends"

MDS classes with significant recommendations overlap, excluding ones under the same top-level class.

None

What is MDS?

Melvil stands for "Melvil Decimal System," named after Melvil Dewey, the famous librarian. Melvil Dewey invented his Dewey Decimal System in 1876, and early versions of his system are in the public domain.

More recent editions of his system are in copyright, and the name "Dewey," "Dewey Decimal," "Dewey Decimal Classification" and "DDC" are registered trademarked by OCLC, who publish periodic revisions.

LibraryThing's MDS system is based on the classification work of libraries around the world, whose assignments are not copyrightable. MDS "scheduldes" (the words that describe the numbers) are user-added, and based on public domain editions of the system.

The Melvil Decimal System is NOT the Dewey Decimal System of today. Wordings, which are entered by members, can only come from public domain sources. The base system is the Free Decimal System, a public domain classification created by John Mark Ockerbloom. Where useful or necessary, wording comes from the 1922 edition of the Dewey Decimal System. Language and concepts may be changed to fit modern tastes, or to better describe books cataloged. Wordings may not come from in-copyright sources.

About | Contact | Privacy/Terms | Help/FAQs | Blog | Store | APIs | TinyCat | Legacy Libraries | Early Reviewers | Common Knowledge | 127,234,943 books! | Top bar: Always visible