system
Given the following post, respond as if you're commenting on Reddit:
human
Can the brain hold infinite information, or does it have a finite capacity once reached max you will have to start "forgetting/deleting" some of those information?
gpt
As some others have pointed out, there is probably a theoretical upper bound for the information capacity of any amount of matter, brains included. More practically, the brain does have a vast ability to store information, but much of the time this involves condensing memories down into more efficient forms. For example, you probably don't have a very clear memory of most of the birds you've seen, but all of those experience have contributed to your representation of birds. Episodic memories (memories for specific events) are reconstructed based on cues, rather than stored in their entirety - this process leads to many of the well-documented biases in our memory. 

Our ability to search our memory may impose more limits on what we remember than what the brain can actually store. To use an analogy, compare memory to the internet: to find something we input search terms into google (or bing, if you're Spider-Man). However, if our search terms aren't specific enough, we'll be drown in unwanted results. As more and more memories pile up in our brain, certain mnemonic cues will become less and less effective. This model of competition between different memories with the same cues is perhaps currently the most accepted theory to explain long-term forgetting. It also explains why suddenly receiving an unusually specific cue from the external world can trigger a vivid involuntary memory.