In combination they define all possible sentences which may be created in the language. If no sign is included the number is positive. The two numbers at the end of the example list are called universal constants. They are the common nouns within the language of algebra - dog, cat, student, etc. Letters in the English alphabet most often represent variables, although Greek letters are sometimes used.
Operators serve the same function as verbs in the English language.
This is common to many computer languages. They let the reader know where one phrase or sentence ends and another begins. Many statements in algebra can be constructed using only the symbols mentioned thus far, although other symbols exist. Some of these symbols will be discussed either later in this chapter and later in the book. Creating sentences Sentences in algebra can be constructed using a few simple rules.