Given problem: What does this bDNhcm5fdGgzX3IwcDM1 mean? I think it has something to do with bases.
bDNhcm5fdGgzX3IwcDM1It looks like a base64 encoded string. Let's decode it.
echo bDNhcm5fdGgzX3IwcDM1 | base64 -dl3arn_th3_r0p35
picoCTF{l3arn_th3_r0p35}