what is hatch ?

A hatch is a pattern of lines and dots that fills an enclosed area.  Some examples of hatch patterns would be brick, wood grain, sand, concrete, diamond plate, insulation, metal, etc.

Help will tell you all about it.

hatch to define in your drawing for material use example the wood....etc

A hatch pattern is not the same as a material in AutoCAD so be careful with your terminology.  Materials are assigned to 3D models.

dear john ... how to apply this on wooden area etc...

Let's clear up one thing at the start.  Are you working in 2D or 3D?The use of the HATCH command is clearly covered in your AutoCAD Help file.  Hatching is normally used in 2D drawings.The use of the Hatch command in a 2D drawing would go something like this.  Start the command.  Pick the hatch Type (Predefined, User Defined or Custom).  Select the Pattern (ex. - Wood).  Color: normally I make this 'ByLayer'.  There are options to change the Angle and the Scale of the hatch pattern too.  I'd suggest enabling the "Associative" hatch option (comes in handy when you stretch a hatched object).  I'd also consider enabling "Create separate hatches" unless you want all hatches you are about to create to be treated like a single entity.  Finally you have to decide between Add: Pick Points or Add: Select Objects.  This will primarily be dependent on what you are hatching (see your Help file).  Once you select one of the options you are returned to your drawing to make your picks.  Press the Enter key when finished.You can use the Hatch contextual ribbon or the old-style Hatch dialog box depending on your preferences.If you can't figure it out I can point you to a couple of websites that have tutorials or you can simply do an online search for "autocad"+"hatch"+"tutorial" and view one of the many YouTube videos on the subject.

John Connor2014-10-01 13:34:44

THANX JOHNY BRO .... U ARE MASTER OF AUTOCAD BRO ..... I TRIED MANY TIMES AND NOW I HAVE 60% TO 70% COMMAND ON HATCH. NOW I CAN USE THIS COMMAND EASILY BUT IF I NEED ANY THING FOR ASK .... I WILL ASK AGAIN ... THANK YOU SOOO MUCH ....   

Let's not get too excited OK?  We're only talking about the Hatch command.

OK SO WHEN SHOULD EXCITED .... DEAR AFTER ASKING HATCH ..... I SOLVED MANY DRWINGS PROBLEMS THATS Y I GET EXCITED :) 

That's good to hear.

hmmm thanx...