Journals are used to create specific transactions within the Expense Unposted Transactions file. The Journal Entry window should not be used unless the user has an understanding of the general ledger. Most transactions should be created within the invoice and payment windows.
The Expenses > Journal Entry window is the same as all the other journal entry windows, except that it posts to the Expenses Unposted Transaction file. An advantage to using the journal entry option through expenses is that you can enter all the expense adjustment journals in this window. This can ease frustration in trying to find an entry that relates to expenses as opposed to looking through hundreds of other journals that have nothing to do with expenses.
Review the Financials > Journals section for details on creating, viewing, and voiding journals.