The O icon of the TTF extension represents the OpenType - TrueType font, which uses the TrueType curve, but supports the advanced features of OpenType. The T icon of the TTF extension represents the TrueType font, which uses the TrueType curve. OpenType features are not supported. The O icon with OTF extension represents OpenType - PostScript font, which uses PostScript curve and supports OpenType advanced features. OpenType is a standard jointly developed by Microsoft and Adobe. There were two major font formats before this. : TrueType and Type 1. The OpenType developed by the two companies includes the two previous formats. TrueType evolves into OpenType - TrueType. On the original basis, OpenType advanced feature support is added, and the extension remains unchanged (TTF). The icon changes from T to O; Type 1 evolves into OpenType - PostScript, which adds OpenType advanced feature support on the original basis. The extension is positioned OTF, and the icon is O. Now Microsoft and Adobe are working hard to kill the previous TrueType and Type 1 fonts. , for example, Windows system fonts have all been converted from TT to OT-TT after Vista (perhaps a transition to OT-PS), and Adobe vigorously promotes OT-PS fonts.

OpenType is also called Type 2 Font is another font format developed by Microsoft and Adobe. It is also an outline font, more powerful than TrueType. One of the most obvious benefits is that it can embed PostScript fonts into TrueType software. It also supports multiple platforms, a large character set, and copyright protection. It can be said that it is a superset of Type 1 and ueType.

OTF main advantages:

1) Enhanced cross-platform functionality

2) Better support for international character sets defined by the Unicode standard

3) Support advanced printing control capabilities

4) The generated file size is smaller

5) Support adding digital signatures to the character set to ensure the integrated function of the file

OTF——opentype compatible font that can be used well on both Mac and PC!

TTF——truetype PC application is better, but Apple compatibility is very poor!

OT became fully popularized in 2006 and 2007. Now, many designers no longer provide TT versions of their works. The TTs on the market are all legacy products. Adobe replaced all its products with OT in 2002.