It's important to choose an appropriate name for the field you're going to add. It should reflect what it will store. For example the date that a payment is effective could be named 'Effective Date'

 You can always change the name later. BUT if you do that after it's been published and there are active data in your application you may lose the data that have already been entered into that field. As a reminder, it's best to backup your data regularly.

There are two kinds of names that a field can have. The first one is the internal name. This field Name is the identifier that is used in scripting, reports and other programming interfaces. It's never really displayed to the user.

The internal name has a few limitations that you need to be aware of:

 •  It must start with a letter, and not a number or symbol. 

 •  It cannot contain spaces. Typically you can get around that by either using underscores _ or using what's called  pascal casing, where two words are separated by a capital letter (e.g. UserName). 

 •  It needs to be fairly short, no more than 50 characters.

The other kind of name is called the Title. This is what the user sees. The field name and field title can be completely different, but you should try to keep them similar to avoid confusion. Unlike field names, Titles can contain spaces and be any length you like – although you should still try to keep them a reasonable length so they will fit into column headers and forms.

When you create a field entry using the Quick Entry, you can enter the Title of the field. The system then automatically creates a Name out of that title.

For example, if we try to create a top-level type definition to store a history of maintenance on your house, you might type in House Maintenance in the Quick Entry. The system will create a field with the name 'HouseMaintenance' and a title 'House Maintenance'. By default all fields are created to hold text, but there are quite a few different data types that you can choose.

Tip : A Data Type refers to the kind of information a field will hold. The different kinds include numbers, text, dates and files. 

 
 You can then enter another top-level type by pressing Alt+Q or Ctrl+Q (depending on the browser) and entering another name. You can enter some fields into that type, or you can click the field to make some changes to the field definition.