Source: Noto Sans Arabic

U+061C Arabic Letter Mark

U+061C was added in Unicode version 6.3 in 2013. It belongs to the block U+0600 to U+06FF Arabic in the U+0000 to U+FFFF Basic Multilingual Plane.

This character is a Format and is mainly used in the Arabic script. It is also used in the scripts Syriac, Thaana.

The glyph is not a composition. It has no designated width in East Asian texts. In bidirectional text it is written as Arabic letter from right to left. When changing direction it is not mirrored. U+061C prohibits a line break before it.

The Wikipedia has the following information about this codepoint:

The Arabic letter mark (ALM) is a non-printing character used in the computerized typesetting of bi-directional text containing mixed left-to-right scripts (such as Latin and Cyrillic) and right-to-left scripts (such as Persian, Arabic, Syriac and Hebrew).
Similar to the right-to-left mark (RLM), it is used to change the way adjacent characters are grouped with respect to text direction, with some difference on how it affects the bidirectional level resolutions for nearby characters.

Representations

System	Representation
Nº	1564
UTF-8	D8 9C
UTF-16	06 1C
UTF-32	00 00 06 1C
URL-Quoted	%D8%9C
HTML hex reference	؜
Wrong windows-1252 Mojibake	Øœ
abbreviation	ALM
Encoding: GB18030 (hex bytes)	81 31 82 38

Elsewhere

Complete Record

Property	Value
Age (age)	6.3 (2013)
Unicode Name (na)	ARABIC LETTER MARK
Unicode 1 Name (na1)	—
Block (blk)	Arabic
General Category (gc)	Format
Script (sc)	Arabic
Bidirectional Category (bc)	Arabic Letter
Combining Class (ccc)	Not Reordered
Decomposition Type (dt)	none
Decomposition Mapping (dm)	Arabic Letter Mark
Lowercase (Lower)	✘
Simple Lowercase Mapping (slc)	Arabic Letter Mark
Lowercase Mapping (lc)	Arabic Letter Mark
Uppercase (Upper)	✘
Simple Uppercase Mapping (suc)	Arabic Letter Mark
Uppercase Mapping (uc)	Arabic Letter Mark
Simple Titlecase Mapping (stc)	Arabic Letter Mark
Titlecase Mapping (tc)	Arabic Letter Mark
Case Folding (cf)	Arabic Letter Mark
ASCII Hex Digit (AHex)	✘
Alphabetic (Alpha)	✘
Bidi Control (Bidi_C)	✔
Bidi Mirrored (Bidi_M)	✘
Composition Exclusion (CE)	✘
Case Ignorable (CI)	✔
Changes When Casefolded (CWCF)	✘
Changes When Casemapped (CWCM)	✘
Changes When NFKC Casefolded (CWKCF)	✔
Changes When Lowercased (CWL)	✘
Changes When Titlecased (CWT)	✘
Changes When Uppercased (CWU)	✘
Cased (Cased)	✘
Full Composition Exclusion (Comp_Ex)	✘
Default Ignorable Code Point (DI)	✔
Dash (Dash)	✘
Deprecated (Dep)	✘
Diacritic (Dia)	✘
Emoji Modifier Base (EBase)	✘
Emoji Component (EComp)	✘
Emoji Modifier (EMod)	✘
Emoji Presentation (EPres)	✘
Emoji (Emoji)	✘
Extender (Ext)	✘
Extended Pictographic (ExtPict)	✘
FC NFKC Closure (FC_NFKC)	Arabic Letter Mark
Grapheme Cluster Break (GCB)	Control
Grapheme Base (Gr_Base)	✘
Grapheme Extend (Gr_Ext)	✘
Grapheme Link (Gr_Link)	✘
Hex Digit (Hex)	✘
Hyphen (Hyphen)	✘
ID Continue (IDC)	✘
ID Start (IDS)	✘
IDS Binary Operator (IDSB)	✘
IDS Trinary Operator and (IDST)	✘
IDSU (IDSU)	0
ID_Compat_Math_Continue (ID_Compat_Math_Continue)	0
ID_Compat_Math_Start (ID_Compat_Math_Start)	0
Ideographic (Ideo)	✘
InCB (InCB)	None
Indic Mantra Category (InMC)	—
Indic Positional Category (InPC)	NA
Indic Syllabic Category (InSC)	Other
Jamo Short Name (JSN)	—
Join Control (Join_C)	✘
Logical Order Exception (LOE)	✘
Modifier Combining Mark (MCM)	✘
Math (Math)	✘
Noncharacter Code Point (NChar)	✘
NFC Quick Check (NFC_QC)	Yes
NFD Quick Check (NFD_QC)	Yes
NFKC Quick Check (NFKC_QC)	Yes
NFKD Quick Check (NFKD_QC)	Yes
Other Alphabetic (OAlpha)	✘
Other Default Ignorable Code Point (ODI)	✘
Other Grapheme Extend (OGr_Ext)	✘
Other ID Continue (OIDC)	✘
Other ID Start (OIDS)	✘
Other Lowercase (OLower)	✘
Other Math (OMath)	✘
Other Uppercase (OUpper)	✘
Prepended Concatenation Mark (PCM)	✘
Pattern Syntax (Pat_Syn)	✘
Pattern White Space (Pat_WS)	✘
Quotation Mark (QMark)	✘
Regional Indicator (RI)	✘
Radical (Radical)	✘
Sentence Break (SB)	Format
Soft Dotted (SD)	✘
Sentence Terminal (STerm)	✘
Terminal Punctuation (Term)	✘
Unified Ideograph (UIdeo)	✘
Variation Selector (VS)	✘
Word Break (WB)	Format
White Space (WSpace)	✘
XID Continue (XIDC)	✘
XID Start (XIDS)	✘
Expands On NFC (XO_NFC)	✘
Expands On NFD (XO_NFD)	✘
Expands On NFKC (XO_NFKC)	✘
Expands On NFKD (XO_NFKD)	✘
Bidi Paired Bracket (bpb)	Arabic Letter Mark
Bidi Paired Bracket Type (bpt)	None
East Asian Width (ea)	neutral
Hangul Syllable Type (hst)	Not Applicable
ISO 10646 Comment (isc)	—
Joining Group (jg)	No_Joining_Group
Joining Type (jt)	Transparent
Line Break (lb)	Combining Mark
Numeric Type (nt)	none
Numeric Value (nv)	not a number
Simple Case Folding (scf)	Arabic Letter Mark
Script Extension (scx)	Syriac Thaana
Vertical Orientation (vo)	R