There are so many different types of hair extensions.
Tape-In Hair Extensions are pre-taped and then taped/glued together on either side of your own hair, and they last 4-8 weeks.
Sew-In Hair Extensions are the most permanent type and most seamless because they are literally sewn into your own hair and cannot come off. Recommended time is 6-8 weeks
Fusion & Pre-Bonded Hair Extensions are bonded to natural hair using different adhesives such as glue, and are considered semi-permanent as they stay in your hair for up to 4 months.
Micro-Link Hair Extensions, also known as micro bead or micro- loop hair extensions, are applied by looping the extensions through the natural hair. Then, you clamp it down with a special tool/clamp, heat, and a metal bead or ring. They are fixed to small sections of natural hair and tightened with this special tool/clamp. They generally last up to 4 months.
Wigs & Hair Pieces come in different forms and are applied to hair topically. To be specific, long full wigs are made to cover your entire head and it essentially completely covers your head and acts as a replacement for your own hair. Typically, real human full wigs can last for up to one year if you take good care of them.
Clip-in Hair Extensions come in a strand of contoured pieces, some long, and some can be cut shorter, with clips that are sewn into the strand. Clip-in hair extensions are the least damaging because they don’t involve any chemicals or heat, etc. They simply clip onto your hair so there is zero damage! With proper care and regular wear, clip-in hair extensions last anywhere from 6 months to one year and sometimes even longer.