Terms starting with "M"
Merkle Tree
PHP 7.0+
A binary tree where each non-leaf node holds the hash of its children, enabling efficient verification that data is intact and untampered.
4mo ago
Data Structures advanced
Metaclass Patterns
Python 3.6+
Metaclasses customize class creation itself — useful for registries, abstract base enforcement, and ORM column collection, but overused where decorators or __init_subclass__ would do.
4mo ago
Python advanced
Memory Pressure Detection
PHP 7.0+
Proactively identifying when a PHP process approaches its memory limit so corrective action can be taken before a fatal error.
5mo ago
Performance intermediate
Mixture of Experts (MoE)
Neural network architecture where a gating network routes each token to a small subset of specialist 'expert' sub-networks, enabling huge total parameter counts at moderate per-token compute cost.
5mo ago
AI / ML advanced
Module Augmentation & Declaration Merging
2.0 Module augmentation lets you extend third-party or global type definitions without modifying their source — adding properties to existing interfaces, modules, or the global scope.
6mo ago
TypeScript advanced
Memory Management in JavaScript
JavaScript uses automatic garbage collection — the engine reclaims memory when objects are no longer reachable. Memory leaks occur when references are unintentionally retained, preventing collection.
6mo ago
JavaScript intermediate
Mixed Content (HTTP on HTTPS)
When an HTTPS page loads resources (images, scripts, stylesheets) over HTTP — browsers block active mixed content and warn on passive, undermining the security of the HTTPS connection.
CWE-319
6mo ago
Security intermediate
Memory-Mapped Files
A file mapped directly into a process's virtual address space — reads and writes go through the OS page cache rather than read()/write() syscalls, enabling fast access to large files and shared memory between processes.
6mo ago
Linux advanced
Mutex vs Semaphore
PHP 7.0+
1
A mutex allows only one thread to access a resource at a time — a semaphore controls access to a pool of N identical resources.
CWE-362
6mo ago
Concurrency advanced
MySQL AUTO_INCREMENT
A column attribute that automatically assigns sequential integer IDs on INSERT — the standard primary key pattern in MySQL.
6mo ago
Database beginner
MySQL charset=utf8mb4
PHP 5.1+
The correct MySQL character set for full Unicode support — including emoji and supplementary characters that the older utf8 charset cannot store.
6mo ago
PHP beginner
MySQL Connection Pooling
PHP 5.1+
1
Reusing database connections across requests instead of opening and closing a new connection on every request.
6mo ago
PHP intermediate
MySQL Date and Time Types
DATETIME, TIMESTAMP, DATE, TIME, and YEAR — each with different ranges, timezone handling, and storage sizes.
6mo ago
Database beginner
MySQL DSN (Data Source Name)
PHP 5.1+
The connection string passed to PDO specifying the database driver, host, port, database name, and charset.
6mo ago
PHP beginner
MySQL ENUM Type
A column that accepts only predefined string values — stored efficiently as integers but with significant schema change pain.
6mo ago
Database beginner
MySQL EXPLAIN
A MySQL query analysis command showing the execution plan — which indexes are used, how many rows are scanned, and where bottlenecks are.
6mo ago
Database intermediate
MySQL FULLTEXT Search
A built-in MySQL search engine supporting natural language and boolean full-text queries on TEXT and VARCHAR columns.
6mo ago
Database intermediate
MySQL GROUP BY and Aggregates
GROUP BY collapses rows with matching column values into one — aggregate functions (COUNT, SUM, AVG, MAX, MIN) compute values per group.
6mo ago
Database intermediate
MySQL Index Types
B-tree, FULLTEXT, SPATIAL, and HASH indexes — each optimised for different query patterns.
6mo ago
Database intermediate
MySQL JOIN Types
INNER JOIN, LEFT JOIN, RIGHT JOIN, and CROSS JOIN — controlling which rows are included when combining tables.
6mo ago
Database beginner