"ext-bcmath":"Increased performance of some operations. Required especially on 32 bit machines. This or ext-gmp are needed for scrambling Temporary Accounts.",
"ext-curl":"Faster HTTP services, e.g. when using InstantCommons, Swift, or Etcd.",
"ext-exif":"Enable processing of EXIF information in file uploads.",
"ext-gd":"Enable thumbnails for file uploads.",
"ext-gmp":"Increased performance of some operations. Required especially on 32 bit machines. This or ext-bcmath are needed for scrambling Temporary Accounts.",
"ext-igbinary":"Enables use of igbinary for serialisation.",
"ext-imagick":"Enables use of imagemagick for image manipulation.",
"ext-memcached":"Enables use of Memcached for caching purposes.",
"ext-mysqli":"Enable the MySQL and MariaDB database type for MediaWiki.",
"ext-pdo":"Enable the SQLite database type for MediaWiki.",
"ext-pgsql":"Enable the PostgreSQL database type for MediaWiki.",
"ext-posix":"Enable CLI concurrent processing, e.g. for runJobs.php.",
"ext-pcntl":"Enable CLI concurrent processing, e.g. for runJobs.php and rebuildLocalisationCache.php.",
"ext-readline":"Enable CLI history and autocomplete, e.g. for eval.php and other REPLs.",
"ext-redis":"Enables use of Redis for caching purposes.",
"ext-sockets":"Enable CLI concurrent processing, e.g. for rebuildLocalisationCache.php.",
"ext-wikidiff2":"Faster text difference engine.",
"ext-zlib":"Enable use of GZIP compression, e.g. for SqlBagOStuff (ParserCache), $wgCompressRevisions, or $wgUseFileCache."