|In Unicode||U+003C < LESS-THAN SIGN (HTML |
|See also||U+2264 ≤ LESS-THAN OR EQUAL TO|
U+2A7D ⩽ LESS-THAN OR SLANTED EQUAL TO used e. g. in Poland
U+226A ≪ MUCH LESS-THAN
|Different from||U+2329 〈 LEFT-POINTING ANGLE BRACKET|
The less-than sign is a mathematical symbol that denotes an inequality between two values. The widely adopted form of two equal-length strokes connecting in an acute angle at the left, , has been found in documents dated as far back as the 1560s. In mathematical writing, the less-than sign is typically placed between two values being compared and signifies that the first number is less than the second number. Examples of typical usage include 1⁄2 < 1 and −2 < 0. Since the development of computer programming languages, the less-than sign and the greater-than sign have been repurposed for a range of uses and operations.
The less-than sign,, is an original ASCII character (hex 3C, decimal 60).
The less-than sign may be used for an approximation of the opening angle bracket, . ASCII does not have angle brackets but are standard in Unicode (U+2329 〈 LEFT-POINTING ANGLE BRACKET (HTML
〈)). The latter is expected in formal texts.
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,, may be used for an approximation of the much-less-than sign, or of the opening guillemet, . ASCII does not have a much-less-than sign.
In the C++ Standard Library, operator
<<, when applied on an output stream, acts as insertion operator and performs an output operation on the stream.
In Ruby, operator
<< acts as append operator when used between an array and the value to be appended.
In XPath the
<< operator returns true if the left operand precedes the right operand in document order; otherwise it returns false.
<<<word is used as a "here string", where
word is expanded and supplied to the command on its standard input, similar to a heredoc.
The less-than sign plus the equals sign,
<=, may be used for an approximation of the less-than-or-equal-to sign, . ASCII does not have a less-than-or-equal-to sign, but Unicode defines it at code point U+2264.
=< means "less than or equal to" (as distinct from the arrow
In Fortran, operator
.LE. means "less than or equal to".
In Bourne shell and Windows PowerShell, the operator
-le means "less than or equal to".
In the R programming language, the less-than sign is used in conjunction with a hyphen-minus to create an arrow (
<-), this can be used as the left assignment operator.
In Bourne shell (and many other shells), less-than sign is used to redirect input from a file. Less-than plus ampersand (
<&) is used to redirect from a file descriptor.
Less-than sign is used in the spaceship operator.
In an inequality, the less-than sign always "points" to the smaller number. Put another way, the "jaws" (the wider section of the symbol) always direct to the larger number.
Edited: 2021-06-18 19:11:53