Legal analysis: all have legal effect. The law does not stipulate what kind of signature to use, as long as it is my signature and the handwriting is clear, it is valid. Even if you sign with a pencil, it is legally binding. Just to preserve the handwriting for a long time, it is generally required to sign with a black pen.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 143 A civil juristic act that meets the following conditions is valid:

(1) The actor has corresponding capacity for civil conduct;

(2) the meaning is true;

(three) does not violate the mandatory provisions of laws and administrative regulations, and does not violate public order and good customs.

Article 469 The parties may conclude a contract in writing, orally or in other forms.

Written form refers to contracts, letters, telegrams, telexes, faxes and other forms that can tangibly express the contents contained.

A data message that can tangibly express its content through electronic data interchange, e-mail, etc. , and can be retrieved at any time, are considered in writing.