So i am reading a book called head first java and in chapter 3 he talks about variables i dont exactly know what bytes and chars are like what type are they do they make a decimal is byte simalar to byte code please help

btw im actually swl so yeah im who posted this

I don't know exactly if Java variables are the same as c# variables, but I'll assume they are. Bytes are the smallest number type, which can store a integer (non decimal) value between 0 and 255. Chars just hold a single character, like:

'a', or '#', or 'G', etc.
I'm not sure you refer to as 'byte' code.

Hope this helps.

Variables are just boxes to store a value in (this works nicely with 'simple' data like integers. For objects, it gets a bit more complicated). You have variables (boxes) of different sizes, see http://java.sun.com/docs/books/jls/seco ... s.doc.html section 4.2.1. A byte-sized variable can store values -128 to 127, etc.
This is especially important if you have not so much room (eg in an embedded device), or if you have storage requirements eg in a file.

In general, you should not care very deeply about the sizes, and just use 'int' for everything, unless -2147483648 to 2147483647 is not large enough :)

Byte code is something different entirely. It is Java program code, translated for your computer (JVM (Java Virtual Machine), to be precise), so it can run the program. Not something you should care much about when still learning about variables.