Which programming languages should one know to modify source code of SCRATCH

I intend to build a custom version of SCRATCH. I am a web-developer and hence not familiar with technologies that开发者_运维知识库 could have used to build scratch.

I see quite a lot technologies used in there such as Java Applets, C, SmallTalk and so on.

Can someone tell me the basic skill-set that's required to modify SCRATCH fro my purpose?

You should get the source code for Scratch: http://info.scratch.mit.edu/Source_Code

Squeak is not a programming language. Looks like I need to know SmallTalk if I want to make changes and for more drastic changes I need to write C code.

Scratch is written in squeak, which is a java implementation of smalltalk.

for 1.4, use squeak. for 2.0, use actionscript. if you want to mod 2.0, read http://scratch.mit.edu/discuss/topic/38970/