What are the different types of non-coding DNA?

Non-coding DNA do not code for proteins but they have several other essential functions. There are many different types of non-coding DNA, each of which performs a different function. These are some of the many types of noncoding DNA:

• Transposons: Transposons make up a sizable component of non-coding DNA. They are capable of changing their location in the genome, altering the size of the cell’s genome, and inducing or correcting mutations when they shift location.  
• Non-coding RNA genes: Non-coding RNA genes include ribosomal RNA (rRNA), messenger RNA (mRNA), and transfer RNA (tRNA), all of which are involved in protein synthesis within the cell. 
• Satellite DNA and telomeres: Located at the ends of all chromosomes, telomeres prevent the ends from getting degraded during DNA replication thereby preserving the structural integrity of the chromosome. 
• Regulatory elements: Noncoding DNA contains several types of regulatory elements. Each of these regulatory elements provide unique binding sites for different types of proteins:  Promoters are regulatory elements that provide binding sites for proteins that carry out transcription; Enhancers provide binding sites for proteins that are responsible for activating transcription; Silencers provide binding sites for proteins that are responsible for repressing transcription; Insulators provide binding sites for proteins that regulate transcription. There are several different types of insulators such as barrier insulators and enhancer-blocker insulators. Each one performs a different function. 
• Introns: Introns are segments of non-coding DNA found between exons or coding sequences. A few introns are responsible for regulating the activity of codons, rRNA, and tRNA, while others are non-functional.  
• Pseudogenes: Pseudogenes are nonfunctional DNA sequences that resemble existing genes. They likely form due to mutations in functional genes that inhibit their transcription.