Less-than sign

The less-than sign is a sign of inequality. The less-than symbol is used in various operations that usually pertain to work being done mathematically or with a programming language. The symbol looks similar to a sideways "V" and is generally used to show inequality between two numbers or expressions. In mathematics, if there are two expressions being compared as an inequality, the less-than symbol usually goes between the two and symbolizes that the first number is less than the second number, for example 5<6 or x<102. The symbol can also be used to the left of a single number to denote the concept of any lesser number, for example "less than 4" would be written as <4. There are other combinations of the less-than symbol and the 'equals' symbols which are also used mathematically and computationally.

The less-than sign (<) is an original ASCII character (hex 3C, decimal 60).

The less-than sign is used for an approximation of the opening angle bracket (⟨). ASCII does not have angle brackets.

In BASIC, Lisp-family languages, and C-family languages (including Java and C++), operator < means "less than".

In Coldfusion, operator .lt. means "less than".

In Fortran, operator .LT. means "less than"; later versions allow <.

In Bourne shell, operator -lt means "less than".

The double less-than sign (<<) is used for an approximation of the much-less-than sign (≪) or of the opening guillemet («). ASCII does not have much-less-than sign.

In Bash, Perl, and Ruby, operator <<EOF (where "EOF" is an arbitrary string, but commonly "EOF" denoting "end of file") is used to denote the beginning of a here document.

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