Global Illumination vs. Radiosity ???

Is Global Illumination (GI) better than Radiosity?

No! Why? Because radiosity is a SUBSET of GI.
They are not two different methods for calculating the light-distribution in a scene.

GI is an opposite of 'local illumination' or 'direct illumination', which
shaders like phong etc use.

Radiosity (Wavelet Radiosity, Hierarchical Radiosity), Photon Mapping and Monte Carlo, are different techniques for calculating the GI of a 3d scene.

GI is a meta-term for radiosity, monte carlo algorith etc.

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Links

(1) Radiosity
http://www-2.cs.cmu.edu/afs/andrew/scs/cs/15-463/pub/www/notes/rad.pdf

(2) GI Methods discussion
http://www-2.cs.cmu.edu/afs/cs/project/classes-ph/860.96/pub/www/montecarlo.mail

(3) Overview Radiosity
http://escience.anu.edu.au/lecture/cg/GlobalIllumination/radiosity/overview_1.en.html
http://escience.anu.edu.au/lecture/cg/GlobalIllumination/index.en.html

(4) Direct Illumination (Shading)
http://escience.anu.edu.au/lecture/cg/Illumination/index.en.html

(5) Very good explaination of Radiosity and GI. Compares a bit Radiosity with Monte Carlo
http://freespace.virgin.net/hugo.elias/radiosity/radiosity.htm

(6) Few slides about GI
http://www.cs.jhu.edu/~cohen/RendTech99/Lectures/Global_Illumination.bw.pdf

(7) Bref history of radiosity
http://www.helios32.com/resources.htm

(8) GI: Wavelet and Hirachical Radiosity, Radiance
http://www9.informatik.uni-erlangen.de:9080/eng/research/rendering/globillum/

(9) Monte Carlo GI
http://www.cgl.uwaterloo.ca/Projects/rendering/Talks/swc/pres26.html

(10) GI links on CGarchitect
http://www.cgarchitect.com/resources/radiosity/default.asp

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Definitions:

radio-
(prefix); concerning waves of force; e.g. light, sound or radio waves
[source: Longman: dictionary of contemporay english]

radiosity (source: link nr. 1)
- integral of emitted radiance plus reflected radiance over a
hemisphere. units: [power/area]
- radiosity is outgoing power per unit area due to emission or
reflection over a hemisphere of directions.

Thus, “radiosity” is both a unit of light and an algorithm.