TLD stands for Top Level Domain, ie ccTLD Swedish. There are various abbreviations depending on what type of TLD.
gTLD stands for Generic Top Level Domain. This is the most common type of top-level domains, here you can find such .com .net, .info, org and many more!
ccTLD stands for Country Code Top Level Domain. This is the top level domain all countries gather under, eg SE for Sweden, .UK for England and .DK for Denmark.
nTLD, stands for New Top Level Domain. This are the new TLDs that have been released in early 2014 and will continue to be under judgment coming years. Tex .club, .yxz, .host, .email and many more.