MDN Web Docs Glossary: Definitions of Web-related terms

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Speed index: Speed Index (SI) is a page load performance metric that shows you how quickly the contents of a page are visibly populated. It is the average time at which visible parts of the page are displayed. Expressed in milliseconds, and dependent on size of the view port, the lower the score, the better.

Web technologies contain long lists of jargon and abbreviations that are used in documentation and coding. This glossary provides definitions of words and abbreviations you need to know to successfully understand and build for the web.

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MDN Web Docs Glossary: Definitions of Web-related terms

Glossary of Terms

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Other

Contribute to the glossary

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MDN Web Docs Glossary: Definitions of Web-related terms

Glossary of Terms

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Other

Contribute to the glossary

See also

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