Helloworld не могу компилировать файл

Microsoft Windows [Versao 6.0.6001]
Copyright (c) 2006 Microsoft Corporation. Todos os direitos reservados.

C:\Users\Sergio>javac
'javac' nao e reconhecido como um comando interno ou externo,
programa operacional ou ficheiro batch.

C:\Users\Sergio>path C:\Program Files\Java\jdk1.8.0_60\bin

C:\Users\Sergio>javac
Usage: javac <options> <source files>
where possible options include:
-g Generate all debugging info
-g:none Generate no debugging info
-g:{lines,vars,source} Generate only some debugging info
-nowarn Generate no warnings
-verbose Output messages about what the compiler is doing
-deprecation Output source locations where deprecated APIs are u
sed
-classpath <path> Specify where to find user class files and annotati
on processors
-cp <path> Specify where to find user class files and annotati
on processors
-sourcepath <path> Specify where to find input source files
-bootclasspath <path> Override location of bootstrap class files
-extdirs <dirs> Override location of installed extensions
-endorseddirs <dirs> Override location of endorsed standards path
-proc:{none,only} Control whether annotation processing and/or compil
ation is done.
-processor <class1>[,<class2>,<class3>...] Names of the annotation processors
to run; bypasses default discovery process
-processorpath <path> Specify where to find annotation processors
-parameters Generate metadata for reflection on method paramete
rs
-d <directory> Specify where to place generated class files
-s <directory> Specify where to place generated source files
-h <directory> Specify where to place generated native header file
s
-implicit:{none,class} Specify whether or not to generate class files for
implicitly referenced files
-encoding <encoding> Specify character encoding used by source files
-source <release> Provide source compatibility with specified release

-target <release> Generate class files for specific VM version
-profile <profile> Check that API used is available in the specified p
rofile
-version Version information
-help Print a synopsis of standard options
-Akey[=value] Options to pass to annotation processors
-X Print a synopsis of nonstandard options
-J<flag> Pass <flag> directly to the runtime system
-Werror Terminate compilation if warnings occur
@<filename> Read options and filenames from file


C:\Users\Sergio>cd Desktop

C:\Users\Sergio\Desktop>javac helloworld.java
javac: file not found: helloworld.java
Usage: javac <options> <source files>
use -help for a list of possible options

C:\Users\Sergio\Desktop>

C:\>javac heloworld.java
javac: file not found: heloworld.java
Usage: javac <options> <source files>
use -help for a list of possible options