There are two ways to export data from an Oracle 10g database. Data Pump or the Export utility.
The export utility has been around for quite some time, and prior to 10g was the only way to export data. But 10g introduced a new method called data pump.
Data Pump seems to be allot faster and more useful, but export is still necessary if you plan to then import the data into an older database. Although I have found you might have to use the version of export utility that is compatible with the database you plan to import into, rather than the ‘new’ version that comes with 10g.
The other thing to note is, that the command line syntax is very different.
With the export utility, to import or export a table you would do something like this.
For Table Exports
exp scott/tiger@db10g OWNER=jones TABLES=scott.emp,
But using data pump, it is like this,
expdp scott/tiger@db10g tables=EMP,DEPT directory=TEST_DIR dumpfile=EMP_DEPT.dmp logfile=expdpEMP_DEPT.log
For Schema Exports
exp scott/tiger@db10g OWNER=jones
Vs
expdp scott/tiger@db10g schemas=SCOTT directory=TEST_DIR dumpfile=SCOTT.dmp
For Full Database Exports/Imports
exp scott/tiger@db10g FULL=Y
Vs
expdp system/password@db10g full=Y directory=TEST_DIR dumpfile=DB10G.dmp
There are of course lots of other options for both export/dump commands so you might want to check this links before rushing ahead.
http://download.oracle.com/docs/cd/B10501_01/server.920/a96652/ch01.htm
ORACLE-BASE – Oracle Database 10g Data Pump.