Exynos
Exynos is a series of ARM-based mobile processors developed by Samsung that are designed to power smartphones, tablets, and other devices. Introduced in 2010, Exynos started as Samsung's in-house solution to compete with Qualcomm's Snapdragon and Apple's A-series chips.
At one time Exynos overtook Snapdragon in performance but could not keep up the pace. They faced much criticism for lagging behind Snapdragon in benchmarks and efficiency. Samsung continues to improve the line, however, it still raises eyebrows when it is featured in Galaxy devices. Furthermore, the South Korean tech giant seems to be adamant about further developing and using its silicon despite the backlash, likely to cut expenses.
Similar to any other chipsets, Exynos comes in different flavours. Currently, it can be divided into 1000 series and 2000 series. The former can be further divided into the 1300 line and 1400. These chips cover the lower midrange space and premium midrange space respectively. Similarly, the Exynos 2000 are dedicated to flagship and semi-flagship phones, where the latter might get one with an "e" moniker to highlight the underclocking of the CPU.
While Samsung has a flagship line of processors of its own, it is still hesitant to use it on its highest line of products such as the S Ultra, and Z series. It opts for the "Snapdragon for Galaxy" chips instead. That might soon change though, as the talks are Samsung is soon planning to be fully self-sufficient in silicons.