The X100 was the first X-series camera to be introduced back in 2011. Characterized by its compact classic rangefinder styling, a unique hybrid optical/electronic viewfinder, high quality 23mm f/2 fixed prime lens and manual controls for shutter speed, aperture and exposure compensation, the X100 (now in its 4th iteration with the X100F) still stands out as being one the most capable compact fixed lens digital cameras available today. The fact that it's simply a gorgeous camera to look at certainly doesn't hurt.
The X-E1 was introduced in 2012 and was positioned under the, then flagship, X-Pro1. It uses the same 16.3 MP CMOS image sensor as the X-Pro1 but uses an electronic OLED viewfinder instead of the hybrid LCD viewfinder. Interestingly, the viewfinder on the X-E1 was actually an upgrade over the X-Pro1's viewfinder. The body design follows the classic rangefinder styling with the viewfinder on the left side of the camera. Despite its age, the X-E1 still offers excellent image quality and when combined with vintage lenses, you have a camera that hearkens back to the film era and is an utter pleasure to shoot with, particularly when shooting in black and white.
The X-E1 has since been followed by the X-E2, X-E2s and now the X-E3
The X-T1 was introduced in 2014 and was Fujifilm's first DSLR styled mirrrorless body. The magnesium body is sealed for weather-resistance against water and dust and is also freezeproof down to -10 degrees C (14 degrees F). The top plate features a wealth of manual controls with dials for exposure compensation, shutter speed and ISO and sub-dials for metering and drive modes. The electronic viewfinder is a large, bright, high resolution OLED unit that offers a 100% view of your scene. The X-T1 uses Fujifilm's 16.3 MP X-trans sensor
which is unique to the X-series cameras.
The X-T1 has since been followed by the X-T2.
The Fujifilm X70 is a large sensor digital compact camera with an 18.5 mm fixed prime lens (28 mm equivalent angle of view (AOV) in 35 mm full frame format. It is part of Fujifilm's X-Series of cameras.
Reviewers have noted the X70's similarity to the Fujifilm X100T. The X70 combines an X-Trans CMOS II sensor with an EXR processor II, and is the smallest of Fujifilm's cameras to be equipped with the company's APS-C sensor. It shares some technology with the Fujifilm X100T (its sensor and auto focus system) but has a wider angle lens and a tilting and fully upwards articulating touchscreen display