Processing, v.s Java:

The Processing environment is written in Java. Programs writen in Processing are also translated to Java and then run as Java programs. Programs written in Java and Processing will usually run faster than programs based on scripting languages like ActionScript and Lingo, which is important for many graphics applications.

Large distinctions between Processing and Java are the Processing graphics library and a simplified programming style that doesn't require users to understand more advanced concepts like classes, objects, or animation and double-buffering (while still making them accessible for advanced users). Such technical details must be specifically programmed in Java, but are integrated into Processing, making programs shorter and easier to read.

My translation:
Processing是建構在Java環境裡. 使用Processing的程式會先被轉成Java, 然後被當成Java程式來執行. 以Java和Processing寫成的程式通常比scripting languages, 例如ActionScript和Lingo, 快上許多, 這對許多的圖形應用程式相當重要.

Processing和Java最大的差別在於Processing的圖形函式庫以及精簡化的程式設計風格, 讓使用者不需要了解許多進階的程式概念, 例如classes, objects, animation和double-buffering(但是進階使用者仍然能使用). 這些程式設計技術在Java必須自行規定, 但是在Processing則是已經被整合在裡面, 使得程式能更簡短而容易閱讀.