Terms starting with "L"
Lines of Code (LOC) as a Metric
The simplest size metric — useful for normalising other metrics and tracking growth, but a poor quality indicator when used in isolation.
6mo ago
Code Quality beginner
Linked List
PHP 5.3+
2
A linear data structure where elements (nodes) store a value and a pointer to the next node, enabling O(1) insertion and deletion at known positions.
6mo ago
Data Structures beginner
Linux File System Hierarchy
1
The standard directory structure of Linux — /etc for config, /var for variable data, /tmp for temporary files, /usr for user programs — knowing it prevents misplacing files.
6mo ago
Linux beginner
Linux Processes
PHP 5.0+
1
Every running program is a process with a PID, memory space, and file descriptors — ps, top, kill, and signals are the essential tools for managing them.
6mo ago
Linux intermediate
Liskov Substitution Principle
1
Subtypes must be substitutable for their base types without altering the correctness of the program.
6mo ago
Code Quality intermediate
List Comprehensions & Generator Expressions
Python 2.0+
Compact syntax for creating lists — [x*2 for x in range(10) if x%2==0] — and lazy generators that avoid materialising the full sequence.
6mo ago
Python beginner
list() / Short Array Destructuring
PHP 5.5+
1
Assigns array elements to variables in a single expression — list($a, $b) or the shorthand [$a, $b] = $array.
6mo ago
PHP beginner
Load Balancing
PHP 5.0+ Distributing incoming requests across multiple servers to maximise throughput, minimise latency, and eliminate single points of failure.
6mo ago
DevOps intermediate
Load Testing
PHP 5.0+
3
Testing system behaviour under expected and peak load conditions to identify performance bottlenecks and breaking points before they affect users.
6mo ago
Testing intermediate
Local File Inclusion (LFI)
PHP 5.0+
1
A PHP include/require driven by user input that can load arbitrary local files, sometimes leading to code execution.
CWE-98 OWASP A3:2021
6mo ago
Security intermediate
7.5
Locale-Aware Formatting
PHP 5.3+
Formatting numbers, currencies, and dates according to locale conventions — 1,234.56 in en-US is 1.234,56 in de-DE, and currency symbols and date formats vary by locale.
6mo ago
i18n intermediate
Log Injection
PHP 5.0+
1
Writing unsanitised user input into log files allows attackers to forge log entries or inject control characters.
CWE-117 OWASP A9:2021
6mo ago
Security intermediate
5.3
Long Method
PHP 5.0+
1
A function or method that is too long to understand in one reading — typically 20+ lines is a signal to split.
6mo ago
Code Quality beginner
Long Parameter List
A function or method with too many parameters — typically 4+ — making calls hard to read and easy to get wrong.
6mo ago
Code Quality beginner
Long Polling & Server-Sent Events (SSE)
PHP 5.0+
1
Server-side push techniques for PHP — long polling holds HTTP connections open until data is ready; SSE streams events over a persistent HTTP response.
6mo ago
Architecture intermediate
Lookahead & Lookbehind
1
Zero-width assertions that match a position based on what precedes or follows — without consuming characters, enabling context-sensitive matching.
6mo ago
Regex advanced
LRU Cache
A fixed-size cache that evicts the Least Recently Used entry when full, implemented with a hash map and doubly linked list for O(1) get and put.
6mo ago
Data Structures advanced
Lazy Loading
HTML5
Defer loading or initialising a resource until it is actually needed, reducing startup cost and memory usage.
7mo ago
Performance beginner
Lazy Objects (PHP 8.4)
PHP 8.4+
PHP 8.4 native lazy objects defer object initialisation until first property access — previously requiring proxy libraries, now built into the engine via ReflectionClass.
PHP advanced