Space travel...

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Every 26 months, the orbits of both Earth and Mars conspire to make travel between the two planets shorter. Launching in one of these windows means the travel time can be reduced to only six months.
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The debate revolves around two terms that describe mission architecture: conjunction and opposition. In a conjunction mission, a spacecraft travels directly from Earth to Mars, and they launch when the mission duration is shortest. In an opposition mission, a spacecraft can visit other destinations along the way, and a shorter mission duration isn’t as imperative. The Venus slingshot to Mars idea is an opposition mission, because the mission would visit Venus first.

(Left) Opposition- (“short stay”) and conjunction-class (“long stay”) Mars missions, respectively, adapted from the Mars Design Reference Architecture (2014). The opposition mission (left) is Earth-Venus-Mars and features an outbound Venus flyby en route to Mars. Optional Earth-return from Venus as a stand alone Earth-Venus Earth (EVE) mission or EarthVenus-Mars abort case is shown with dotted line.

https://www.universetoday.com/147009/instead-of-going-straight-to-mars-astronauts-should-make-a-slingshot-past-venus-first/

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The researchers suggest that a mission that includes a Venus stopover would provide benefits both to NASA and the astronauts aboard such craft. They note that stopping by Venus would greatly reduce fuel costs because the spacecraft could use Venus's gravity as a springboard to Mars. They also note that taking the Venus to Mars route would allow the spacecraft to return to Earth sooner should something go wrong.

https://phys.org/news/2020-07-case-slingshotting-venus-mars.html