The + and - signs are additions and deletions, to see what happens when I make a 1000 lines of changes, I've typed 5 new lines in a file, copied the block 10 times to create 50 lines, copied that new block 5 times to create 250 lines and copied the 250 line block 4 times to get to a 1000 new lines.
This is the result after the merge:
git pull
Updating 992208e..5ccbb1e
Fast-forward
todo.txt | 998 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 997 insertions(+), 1 deletion(-)As you can see a lot more + signs than normally (approximately 185), not a 1000 + signs, but it filled the entire width of the screen to show that it's a big change.