Section headings Wikipedia:Manual of Style

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section headings follow same guidance article titles (above), , should presented in sentence case (funding of unesco projects) not title case (funding of unesco projects). other provisions relating article titles apply section headings well.

use equal signs around section heading: ==title== primary section; ===title=== subsection; , on =====title=====. (=title= never used.) heading must on own line, 1 blank line before it; blank line after optional , ignored (but not use 2 blank lines, before or after, because add unwanted visible space). spaces around title (e.g. == title ==) optional , ignored.

in addition:

headings should not refer redundantly subject of article (early life, not smith s life or life) or higher-level headings, unless doing shorter or clearer.
headings should not contain links, part of heading linked.
section headings should preferably unique within page; otherwise section links may lead wrong place, , automatic edit summaries section edits ambiguous.
citations should not placed within, or on same line as, section headings.
headings should not contain images, such flag icons or <math>.
headings should not phrased questions.
avoid starting headings numbers (other years), because can confusing readers auto-number headings preference selected.

an invisible comment on same line heading should inside == == markup:

before changing section heading, consider whether might breaking existing links section. if there many links old section title, create anchor title ensure links still work. similarly, when linking section of article, leave invisible comment, @ heading of target section, naming linking articles if section title altered linking articles can fixed. example:

heading-like material:

several of provisions applicable content serves same basic function heading. example, headers of tables (and of table columns , rows) should follow above advice sentence case, redundancy, images, , questions. however, table headings can incorporate citations , may begin with, or be, numbers. unlike page headings, table headers not automatically generate link anchors. aside sentence case in glossaries, heading advice applies term entries in description lists. if using template-structured glossaries, terms automatically have link anchors, not otherwise. citations description list content go in term or definition element, needed.

cite error: there <ref group=lower-alpha> tags or {{efn}} templates on page, references not show without {{reflist|group=lower-alpha}} template or {{notelist}} template (see page).