Similar looking variables

This is the list of similar looking variables, found across the application. They might be confused one with the other.

One _ : the difference in the name is only _ (underscore); Case : the difference in the name is only the case; One letter : the difference in the name is only one letter;One digit : the difference in the name is only one digit;Partial inversion : the variable name may be broken in two pieces, which were inverted;

Variable	Variables	Reason
$_temp	$temp	One _
$_data	$data	One _
$file_path	$filepath	One _
$field_name	$fieldname	One _
$field_name	$field_names	One letter
$_str	$str	One _
$val_str	$valstr	One _
$max_age	$maxage	One _
$_config	$config	One _
$_mimes	$mimes	One _
$_error	$error	One _
$old_str	$oldstr	One _
$file_data	$filedata $_filedata	One _
$_file	$file	One _
$new_file	$newfile	One _
$method_name	$methodname	One _
$_doctypes	$doctypes	One _
$_level	$level	One _
$_filedata	$file_data $filedata	One _
$res	$RES	Case
$res	$resp $regs	One letter
$out	$OUT	Case
$lang	$LANG	Case
$uri	$URI	Case
$uri	$uris	One letter
$ext	$EXT	Case
$ext	$text	One letter
$sec	$SEC	Case
$obj	$OBJ	Case
$point1	$point2	One digit
$point2	$point1	One digit
$key2	$key	One digit
$val2	$val	One digit
$rad1	$rad	One digit
$key	$keys $key2	One letter
$val	$vals $val2	One letter
$sql	$sqls	One letter
$str	$_str $fstr	One letter
$var	$vars	One letter
$old	$bold	One letter
$chr	$char	One letter
$url	$urls	One letter
$fnc	$func	One letter
$par	$pair $pars	One letter
$typ	$type	One letter
$day	$days	One letter
$sig	$sigs	One letter
$age	$page	One letter
$arg	$args	One letter
$att	$atts	One letter
$rad	$rand $read $rad1	One letter
$all	$call	One letter
$len	$slen	One letter
$for	$form	One letter
$name	$pname $mname	One letter
$line	$lines	One letter
$item	$items	One letter
$type	$types	One letter
$path	$paths	One letter
$mode	$model	One letter
$data	$_data	One letter
$call	$calls	One letter
$info	$finfo	One letter
$file	$files $_file	One letter
$time	$mtime	One letter
$temp	$_temp	One letter
$word	$words	One letter
$char	$chars	One letter
$mime	$mimes $mtime	One letter
$pars	$parts	One letter
$prop	$props	One letter
$year	$years	One letter
$rule	$rules	One letter
$list	$plist	One letter
$perm	$perms	One letter
$hour	$hours	One letter
$unit	$units	One letter
$field	$fields	One letter
$table	$tables	One letter
$value	$values	One letter
$error	$_error $errors	One letter
$level	$_level	One letter
$param	$params	One letter
$regex	$regexp	One letter
$chunk	$chunks	One letter
$mimes	$_mimes	One letter
$month	$months	One letter
$theta	$thetac	One letter
$result	$results	One letter
$valstr	$val_str	One letter
$object	$cobject $mobject	One letter
$column	$columns	One letter
$config	$_config	One letter
$helper	$helpers	One letter
$header	$headers	One letter
$expire	$expires	One letter
$maxage	$max_age	One letter
$oldstr	$old_str	One letter
$minute	$minutes	One letter
$second	$seconds	One letter
$default	$defaults	One letter
$_ci_var	$_ci_vars	One letter
$section	$sections	One letter
$segment	$segments	One letter
$newfile	$new_file	One letter
$content	$contents	One letter
$filepath	$file_path	One letter
$callback	$callbacks	One letter
$doctypes	$_doctypes	One letter
$filedata	$file_data $_filedata	One letter
$log_error	$log_errors	One letter
$attribute	$attributes	One letter
$start_day	$start_days	One letter
$fieldname	$field_name	One letter
$migration	$migrations	One letter
$data_type	$data_types	One letter
$block_size	$block_sizes	One letter
$methodname	$method_name	One letter
$sqlsrv_error	$sqlsrv_errors	One letter