Like lots of photographers. I shoot my photos producing RAW files and not the poorly rendered JPEG files produced by many point and shoots and cell phone cameras, you know, the horrendous looking photos on FaceBook and Twitter (Instagram, etc.) that people rave about. JPEG files can be beautiful when the output is properly configured and suitable to a purpose. I know many people that shoot using files "straight out of camera" (SooC/SOOC). I have one camera setup for JPEG only myself. JPEG files though can only contain so many colors and only so much data being only an 8 bit file, so the data is compressed in a lossy fashion plus they are "flattened" meaning the exposure, white balance, and other photo attributes are locked and not available for editing. The lossy part means that some data is thrown away by design. Gone forever. RAW files contain every bit of data the camera can record, good or bad, EVERY bit of data recorded by the camera's sensor. You have options to record compressed lossless or uncompressed for most cameras. They are 14 bit or 16 bit files too so there is a lot of data in a RAW file. Much more.
So lots of image makers of still and video photography shoot in RAW to allow for more creative control. Each camera manufacturer supplies their own version of RAW format, Nikon's for instance uses a NEF extension to their files, Fuji uses RAF and so it goes. There is no standard either so RAW formats ARE very different from each other meaning conversion is specific for each format and have to deal with how each manufacturer stores their RAW data. There is one format thats "open source" meaning all the formatting is provided as a template. Its uses a DNG file extension (means Digital Negative) and it was developed by Adobe, arguably the largest supplier of photo editing software, but only a few companies use it and it has not really caught on. Mostly because the manufacturers sort of bury their "secret sauce" for color rendition, exposure and dynamic range to name a few items, in their RAW source files. This is how different cameras render photos differently. Why I prefer Nikon and Fuji over Canon for instance. Why one camera's color red is over done and another is perfect when shooting the same picture. Adobe's DNG and their RAW conversion principles follow more of a middle ground attempt to appease everyone, although its said that some companies do supply Adobe with their RAW "formulas" so they do work better with their products than others.
Yes, each manufacturer supplies a RAW conversion tool with their cameras. Updated for each model. Yes, each new model can and often does have changes from previous RAW versions since new models support new features. Locked into one RAW converter is fine if you use one camera brand forever. Not so good if you use many brands or make a change later on. So the market tends to use broader based products like Adobe's Camera RAW (ACR) software which offers RAW support for many cameras and models but its expensive in time and money to support each manufacturer at the same level. Its extremely tough for one product to support so many versions. So for the most part, users soldier on with "good enough" results. ACR has legions of followers. Many of us spend hours correcting for and adding what should be there in the first place.
There does come a time though where as a working photographer, where you HAVE to have better RAW conversion. Good enough just doesn't cut it. That time comes when you get "muddied" features, smeared colors and lack of detail. When your file is first opened and it just looks flat. When it gets no better in subsequent versions. No fixes. Or where the camera you use is openly ignored by Adobe because it's technology is a bit different and they just don't deem the cost worth it to support it properly.
When that time comes, you start to look around at options. Part II will speak to those options. Two years ago the options were minimal. And not very well coded or implemented. Today its different. Less buggy code, better designs and there is a nice little cottage industry supplying top notch software at reasonable prices. Some larger players are also getting more involved.