It is called diffusion. Density of the ocean is highly depending on the amount of salt in it which chages frequently because of rain, heat etc. So diffrences in amount of salt occurs in different parts of the oceans. So water in the ocean moves to equalize the amount of salt in itself.
In a data table, units of measurement should be indicated in the headings of the columns where the data values are listed. This shows that the indicated unit applies to all the data values listed in the column.
