Leet

Leet (or "1337"), also known as eleet or leetspeak, is an alternative alphabet for many languages that is used primarily on the Internet. It uses various combinations of ASCII characters to replace Latinate letters. For example, leet spellings of the word leet include 1337 and l33t; eleet may be spelled 31337 or 3l33t.

The term leet is derived from the word elite. The leet alphabet is a specialized form of symbolic writing. Leet may also be considered a substitution cipher, although many dialects or linguistic varieties exist in different online communities. The term leet is also used as an adjective to describe formidable prowess or accomplishment, especially in the fields of online gaming and in its original usage – computer hacking.

History

Leet (programming language)

Leet (or L33t) is an esoteric programming language based loosely on Brainfuck and named for the resemblance of its source code to the symbolic language "L33t 5p34k". L33t was designed by Stephen McGreal and Alex Mole to be as confusing as possible. It is Turing-complete and has the possibility for self-modifying code. Software written in the language can make network connections and may therefore be used to write malware.

Language specification

The basic data unit of L33t is the unsigned byte (big-endian), which can represent ASCII values and numbers in the range 0-255.

The source code is in "l33t 5p34k" and words are separated by spaces or carriage returns. The language uses 10 opCodes and each word in the source code is translated into an opCode by adding all the digits in the word together, e.g. l33t = 3 + 3 = 6. It is not necessary to use anything but digits in the code.

The language utilises a 64K block of memory, and 2 pointers - a memory pointer and an instruction pointer. The l33t interpreter tokenizes all the words in the source to create a sequence of numerical opCodes, and places them in order into the memory block, starting at byte 0. The instruction pointer will keep incrementing until it encounters an END. The memory pointer starts at the first byte after the instructions. Memory "wraps": incrementing the memory and the instruction pointer past 64K will cause it to run around to byte 0, and vice versa.

Join (SQL)

A SQL join clause combines records from two or more tables in a relational database. It creates a set that can be saved as a table or used as it is. A JOIN is a means for combining fields from two tables (or more) by using values common to each. ANSI-standard SQL specifies five types of JOIN: INNER, LEFT OUTER, RIGHT OUTER, FULL OUTER and CROSS. As a special case, a table (base table, view, or joined table) can JOIN to itself in a self-join.

A programmer writes a JOIN statement to identify records for joining. If the evaluated predicate is true, the combined record is then produced in the expected format, a record set or a temporary table.

Sample tables

Relational databases are usually normalized to eliminate duplication of information such as when objects have one-to-many relationships. For example, a Department may be associated with a number of Employees. Joining separate tables for Department and Employee effectively creates another table which combines the information from both tables. This is at some expense in terms of the time it takes to compute the join. While it is also possible to simply maintain a denormalized table if speed is important, duplicate information may take extra space, and add the expense and complexity of maintaining data integrity if data which is duplicated later changes.

Join (topology)

In topology, a field of mathematics, the join of two topological spaces A and B, often denoted by , is defined to be the quotient space

where I is the interval [0, 1] and R is the equivalence relation generated by

At the endpoints, this collapses to and to .

Intuitively, is formed by taking the disjoint union of the two spaces and attaching a line segment joining every point in A to every point in B.

Properties

is homeomorphic to the reduced suspension

of the smash product. Consequently, since is contractible, there is a homotopy equivalence

Examples

Relational algebra

Relational algebra, first described by E.F. Codd while at IBM, is a family of algebras with a well-founded semantics used for modelling the data stored in relational databases, and defining queries on it.

The main application of relational algebra is providing a theoretical foundation for relational databases, particularly query languages for such databases, chief among which is SQL.

Introduction

Relational algebra received little attention outside of pure mathematics until the publication of E.F. Codd's relational model of data in 1970. Codd proposed such an algebra as a basis for database query languages. (See section Implementations.)

Five primitive operators of Codd's algebra are the selection, the projection, the Cartesian product (also called the cross product or cross join), the set union, and the set difference.

Set operators

The relational algebra uses set union, set difference, and Cartesian product from set theory, but adds additional constraints to these operators.

It's (album)

It's is the second mini-album by South Korean boy group Teen Top. The mini-album was released on January 9, 2012 and contains six tracks. "Going Crazy" was used as the promotional track for the mini-album. The mini-album debuted at number 3 on the Gaon Album Chart on January 18, 2012.

Background

With six tracks, the album was produced by Brave Brothers Kang Dong Chul, who took on not only the production, but writing, composition, and mixing processes as well to ensure its high quality.

"It's" is filled with an intro, an instrumental, a remix of the title track, and another three full music tracks. The mini album starts off with Teen Top's self-titled intro before it moves to its title track, "Going Crazy". The songs are followed by "Where's Ma Girl" and the slower "Girl Friend". The mini album then moves on to a R&B version of "Going Crazy" before adding another instrumental of the title track.

Track listing

Chart performance

Their title track, "Going Crazy" was the #1 most downloaded ringtone in Korea early January 2012. On January 20, the weekly mobile ringtone chart on major Korean portal site Nate.com revealed that TEEN TOP’s “Going Crazy” triumphed T-ara‘s “Lovey Dovey” to secure the #1 spot.

"Awesome"

Self-described as "Part band, part art collective." While they reject the "rock band" label, Lane Czaplinski, artistic director of On the Boards remarks, "If they are not rock musicians, "there is rock payoff." Czaplinski has compared them to Polyphonic Spree

"Awesome" began as a cabaret act thrown together by seven experienced fringe theater actors. Although they continued to perform often in theatrical venues, their identity as a band and cabaret act has eclipsed their status as actors. Around October 2003, several future members of "Awesome" played together in a They Might Be Giants tribute to raise money for Seattle's Open Circle Theater. Their very first performance under the name "Awesome" (with just Ackermann, Mosher, Nixon, and Osebold) was in Seattle at Annex Theater's monthly cabaret "Spin the Bottle" On February 6, 2014, and their first full-septet performance as "Awesome" was in the Jewelbox theater at Belltown bar the Rendezvous on June 30, 2014. Their first major production was Delaware (first a multi-media stage production and later an album). Gigs as a band have included performing on bills with Harvey Danger,A. C. Newman,U.S.E.,The Presidents of the United States of America, and The Long Winters.