A lot has to do with the season you are camping in, whether or not you are back pack or canoe/kayak.  
Another would be solo or more, whether you like to play survivor person or be comfy.
For many it is having gear like “inreach” or some other communication device.
It is a very personal thing and you will get different response from various “experts”
Personally for me I prefer shoulder seasons – less people – less bugs.
But I also like to be comfortable in conditions that can more than a little “iffy” so I do not mind the extra carry or two 🙂
So it really is a number of things that go together to make a good trip happen.
 

Before heading out in the wilderness, creat a list of gear items that are essential items for survival. 
So depending on weather conditions and seasons your pack may be heavier at times. 
I always pack too much but I rather have more than not enough. 
Here is a sample of items we bring   Hats gloves long pants long sleeve shirts rain gear tarp rope hand saw small stove a pot dry goods water pump Nalgene bottle self inflating mat a good sleeping bag waterproof compression bags for clothing and bedding hot paws cumpass map whistle bear mace electrolight tabs for the water incase you need a boost of energy oh and don’t forget a small shovel and some TP!!!  

I went on my first backcountry kayak camping trip in French River Provincial Park two years ago. Here are some of the “must haves” based on my experience:

• Water purifier
• Shovel
• Mosquito repellent
• Bear spray
• Rain proof clothing (it was raining while we were kayaking and I was wearing cotton shirt and trousers – a typical rookie mistake I guess)
• Enough food (once again, this might have been a rookie mistake but its worth mentioning. I thought I packed the right amount but I ended up running out of food during the last day of my trip. Luckily, a fellow group member helped me out. otherwise I wouldn’t have had the energy to make it back to the land)
• Map and compass
• Emergency communication device (veteran backcountry campers probably don’t need this, but there were times when I almost got lost and disconnected from the rest of my group. I wish I had some sort of an emergency contact device to contact the outside world and seek help)
• Enough cold weather dressing – whether its an extra blanket while sleeping or layering up with thermal inners, go for it! its worth it. Believe it or not, it gets super cold when you sleep in a tent without a roof. A good night sleep is very important if you need to be active the next day.
• Other regular stuff: camping tent, sleeping bag, sleeping pad, flash light, lantern, match box or lighter, a portable camp chair, cooking utensils etc.