YCs

YCs is the term used to refer to the group of startups that have participated in Y Combinator (YC), a seed accelerator program based in the United States. YC aims to help early-stage companies with funding, mentorship, and a structured program that accelerates product development and market entry. The program culminates in a Demo Day where founders present to a curated audience of investors.

YC was founded in 2005 in Mountain View, California, by Paul Graham, Jessica Livingston, Trevor Blackwell, and Robert T. Morris. Since then it has funded thousands of startups and built a global network of alumni and mentors. The core YC program provides seed funding in exchange for equity, typically in a three-month cycle that includes weekly group office hours, mentor sessions, and peer feedback. The experience emphasizes rapid iteration, customer development, and scalable business models. In addition to the accelerator, YC runs other initiatives such as Startup School, a free online course for startups, and YC Continuity, a growth-stage investment fund.

Notable YCs include Airbnb, Dropbox, Stripe, Reddit, DoorDash, Instacart, and Coinbase. The YC ecosystem has influenced startup culture by popularizing equity-based seed funding, structured accelerators, and a strong emphasis on network effects and speed. Critics point to the selective nature of the program and the heavy equity stake, while supporters emphasize the network, mentorship, and capital access that YC provides.