The United Earth Starfleet of the 22nd century used a simple forward-facing "pointer" shaped pennant, with a round backdrop, that was reminiscent of symbols used by NASA in the 20th and 21st centuries. The original design for the Starfleet uniform of that era did not include this symbol, unless it was a crewperson assigned to Starfleet Command, who wore the insignia as their assignment patch on the left shoulder. In a later uniform revision of the 2160s, personnel wore the Starfleet patch on their right shoulder as well as the left shoulder assignment patch. (ENT: 運命の飛行、最後のフロンティア、TNG: ホテル・ロイヤルの謎)
Shortly after the founding of the United Federation of Planets in 2161, a solid silver delta was worn on the left breast of the uniform, with individual assignment patches worn on both shoulders. (スター・トレック：BEYOND) This simple silver design would see a brief resurgence in the early 2380s. (LD: 第二種接近遭遇)
In the mid-23rd century, a simplified pennant version of the delta was used on Federation starships and installations. This symbol for Starfleet was not worn on uniforms, which again only displayed an individual crewperson's assignment patch. Some starships, such as the Defiant, had an assignment patch similar to this symbol. (TOS: 宇宙軍法会議、ENT: 暗黒の地球帝国・前編、暗黒の地球帝国・後編)
The delta insignia came into usage for much of Starfleet's exploration division in the early to mid 23rd century. A starburst insignia was used by flag officers and administrative support staff of fleet headquarters and starbases. Some Constitution級 starships during the mid-23rd century used a variety of insignia unique to each ship. The Enterprise maintained the delta as her insignia and assignment patch. (TOS: 光るめだま、宇宙軍法会議、宇宙の巨大怪獣、細菌戦争の果て、ENT: 暗黒の地球帝国・後編、スター・トレック、DIS: バルカンの挨拶)
By the mid-2270s, while installations and starships, such as Epsilon IX station, maintained their individual assignment patches, Starfleet Command had adopted a new Starfleet insignia, a symbol previously used as the assignment patch of the USSEnterprise, and prior to that, the USSKelvin and USSFranklin. (劇場版スタートレック、スター・トレック、 スター・トレック：BEYOND) Specifically, the command division insignia, with the MACO five-pointed star contained in the arrowhead, was most often used, although a version omitting the internal star gained prominence as well. This arrowhead shape, with similar asymmetry as the previous incarnation, had roots in history as being used in a basic form on the United States armed forces space command ratings badge and unit insignia, and on UESPA exploration vessels, such as the Friendship 1, in the 21st century. This symbol was now pointed up when worn on the chest or shoulder of uniforms, as well as displayed in signage. The arrowhead was faced forward when used as hull decoration. This symbol eventually phased out all assignment patches by the late 2270s, and remained in use for some Starfleet divisions well into the 24th century. The metal badge version of this symbol became Starfleet's first combadge as well. (スタートレック2：カーンの逆襲、TNG: 亡霊戦艦エンタープライズ“C”、VOY: 終焉の星)
In the 2340s, a more stylized version of the symbol, the familiar arrowhead without any internal symbology within the shape, and mounted on an oval field, was incorporated into uniforms. A metal badge of this emblem, again serving as a combadge, was worn on the uniform chest. This symbol also became common in starship hull pennants. (TNG: 未知への飛翔、戦士の休息)
By the 2370s, a newer version was created for use as a combadge, with a stylized trapezoidal background. Starship hull pennants of this era began using a simplified version of the arrowhead alone, without a background. (スタートレック：ジェネレーションズ、DS9: ドミニオンの野望・前編; VOY: 遥かなる地球へ; スタートレック：叛乱) Starfleet briefly adopted the simplified silver version as part of the uniform used in the early 2380s before switching back to the version used in the 2370s. (LD: 第二種接近遭遇、PIC: ネペンテ)
By 2399, a hollow, outlined version of the arrowhead in silver with two dark, irregular stylized vertical trapezoids descending from behind was the Starfleet insignia. (PIC: 地図と伝説) This is similar to a version of the insignia used in several alternate timelines during the same time period, which used gold. (TNG: 永遠への旅、DS9: 父と子、VOY: 過去を救いに来た男、道は星雲の彼方へ)
In the alternate reality created by Nero's incursion, Starfleet had done away with the assignment patches by the 2250s. Instead, the fleet was united behind a gold arrowhead, slightly modified from the assignment patch of the USS Kelvin, with a shallow arrowhead indentation on the inside (as seen on dress uniforms). The insignia used on starships was a silver arrowhead with a hollow division symbol inside the arrowhead, similar to the assignment patches used aboard the prime timeline's USS Enterprise. (スター・トレック)
In the mirror universe, a dagger impaling the Earth was the symbol of the Terran Empire, and, as such, was used as the insignia of the Imperial Starfleet. (ENT: In a Mirror, Darkly、In a Mirror, Darkly, Part II; DIS: Despite Yourself; TOS: イオン嵐の恐怖)
In the Barash-created false-future illusion experienced by William T. Riker in 2367, the symbol used in the Starfleet combadge consisted of the arrowhead, either silver or gold, with four horizontal bars behind indicating the rank of the individual by the number of bars that were gold or silver. (TNG: Future Imperfect) This version was also in use in an alternate quantum reality visited by Worf in 2370. (TNG: Parallels)
In several alternate timelines observed by Starfleet personnel, new variations of this symbol existed. In the 2390s and 25th century, Starfleet personnel were known to wear a hollow, outlined version of the arrowhead with two irregular stylized vertical trapezoids behind it as their badge. (TNG: All Good Things...; DS9: The Visitor; VOY: Timeless、Endgame)
Further in the future, 29th century Starfleet had a rotated version of the arrowhead shape, with the bottom half filled in with a mirror of the top point of the shape. In 29th century timeship hull decorations, the arrowhead was shown pointing backwards from the direction of motion for the first time, possibly because of the vessels' capability for time travel. (VOY: Future's End、Future's End, Part II、Relativity)
|時代：||2140年代～2160年代初期 • 2160年代中盤 • 2230年代 • 2230年代後期～2250年代 • 新時間軸2250年代～2260年代 • 2250年代中盤～2270年代初期 • 2270年代中盤 • 2270年代後期～2350年代 • 2350年代～2370年代 • 2360年代後期～2370年代初期 • 2370年代～2380年代初期 • 2380年代初期 • 2380年代中盤 • 2390年代 • 32世紀|
|種類：||カジュアルな服装 • 別の時間軸の制服 • テラン帝国の軍服 • 新時間軸の制服 • 架空の宇宙艦隊の制服|
|関連項目：||アサイメント・パッチ • 連邦ブルー • 宇宙艦隊の記章 • 宇宙艦隊の階級 • 宇宙艦隊の勲章 • テラン帝国の階級 |
MACOの軍服と装備 • 患者着 • アルファ宇宙域の制服 • キセニロン
From the (2nd ed., p. 1) |3=Star Trek Encyclopedia (3rd ed., vol., p. 365)| (3rd ed., p. 1)}} |4=Star Trek Encyclopedia (4th ed., vol., p. 365)| (4th ed., p. 1)}} |Star Trek Encyclopedia (? ed., vol. 1, p. 365)}}, "The distinctive arrowhead symbol used on Starfleet uniforms was first created by Original Series costume designer William Ware Theiss for the The Cage in 1964. Three versions of the original symbol were created, used for command personnel, science specialists, and engineering staff. (A fourth version, featuring a red cross, was occasionally worn by Christine Chapel.) During the original Star Trek series, it was generally assumed that the arrowhead symbol was unique to テンプレート:Enterprise, and that other starships had different insignia for their uniforms."
Another version, which appeared only in "The Cage", had a unique symbol of a box, open on the wearer's left, with a "C" shape inside. Only two crewmembers were seen wearing this unique insignia; both were on the bridge with one standing like a guard at the turbolift doors, and the other standing at times next to Captain Pike's chair. This unique insignia's department/division was never mentioned on screen; it was dropped in the second pilot, Where No Man Has Gone Before, and never appeared again.
A memo from Bob Justman dated 18 December 1967 discusses the Starfleet arrowhead emblem and individual crew patches. It states "all Starship personnel wear the Starship emblem that we have established for our Enterprise Crew Members to wear," meaning that the arrowhead was always meant to be the emblem for all of Starfleet. Further, the crew of the Antares was the "equivalent of the Merchant Marines or freighter personnel" and other emblems should be counted as production mistakes. 
Reference works, such as the Star Trek: The Next Generation Technical Manual (p. 3), suggest that the Starfleet-wide adoption of the Enterprise emblem was probably to honor the ship and her crew for their successful and historic five-year mission. Considering that one of Star Trek's long-held influences is the Age of Sail, it may be a reference to the British Royal Navy's adoption of Nelson Chequer – the particular coloration of the ships of Admiral Horatio Nelson – on all of its ships after the Battle of Trafalgar. In a form of fact emulating fiction (and vice-versa), the US Air Force Space Command badges have a delta arrowhead very similar to the 1960s-designed Enterprise insignia, while the United Earth Starfleet insignia seems to be a deliberate synthesis between the TOS era pennant and the NASA logo. Several other space agencies (Roscosmos, JAXA, CNSA, ISRO) use a variation of the 'vector' shape in their logos as well.
The Star Trek Encyclopedia further notes: "This changed in 劇場版スタートレック, when a modified emblem, designed by Robert Fletcher, was used not only on Enterprise crew members, but on all Starfleet personnel. We therefore assume that at some point after the original Star Trek series, the Enterprise emblem was adopted for the entire Starfleet. The feature film insignia (in a couple of variations) was used for the movies set in the Kirk era, as well for 新スタートレック flashback sequences involving Picard's cadet days. Yet another variation was created for 新スタートレック's first season by Theiss, in conjunction with Rick Sternbach and Mike Okuda. This version was also used on スタートレック：ディープ・スペース・ナイン. Most recently. Starfleet officers wear a version designed by John Eaves and Bob Blackman, first seen in スタートレック：ジェネレーションズ. Additionally, two hypothetical future versions have been seen. One, designed by Okuda, was seen in Future Imperfect and Parallels, while another, designed by Eaves, was used in All Good Things... and The Visitor. Still more variants were added for the Kelvin timeline for スター・トレック and スター・トレック：イントゥ・ダークネス."
The 29th century insignia is referred to as the "far future Starfleet" symbol in the Star Trek Sticker Book, and was designed by Richard James and Rick Sternbach. (p. 14)
Several patches were sold off on the It's A Wrap! sale and auction on eBay. 
Following the announcement of the logo of the United States Space Force, a division of the Department of the Air Force, a number of sources noted its similarity to the Starfleet insignia, though others pointed out that the design appeared to based on the logo of the Air Force Space Command, which was phased out in place of the new Space Force.