A field with Numeric data type (see Data types) can contain a variety of numbers, including ones with decimal places.
The formatting properties available on the General page are:
Width (choose from Byte, Integer, Long, Currency, Single, Double - the default is Long - see Width properties in numeric fields)
Initial Value (enter a default value that will automatically appear in this field every time a new record is created, unless another value is entered instead of it - Initial value)
Caption (enter a caption to replace the field name above the column in Table View - see Captions)
Validation Rule (set a rule to validate possible data entries - see Validation rule)
Validation Text (write a display message for cases of invalid data - see Validation text)
Required (when checked a value is required in field - see Required property)
Index (choose from Primary Key, Indexed, No Index & Indexed (Unique) - see Indexes and primary keys)
The formatting properties available on the Format page are specifically connected with the various types of number - see Number formats in database.